Update copyrights for 2020

Backpatch-through: update all files in master, backpatch legal files through 9.4

src/backend/access/rmgrdesc/brindesc.c

@@ -3,7 +3,7 @@
  * brindesc.c
  *	  rmgr descriptor routines for BRIN indexes
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/clogdesc.c

@@ -3,7 +3,7 @@
  * clogdesc.c
  *	  rmgr descriptor routines for access/transam/clog.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/committsdesc.c

@@ -3,7 +3,7 @@
  * committsdesc.c
  *	  rmgr descriptor routines for access/transam/commit_ts.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/dbasedesc.c

@@ -3,7 +3,7 @@
  * dbasedesc.c
  *	  rmgr descriptor routines for commands/dbcommands.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/genericdesc.c

@@ -4,7 +4,7 @@
  *	  rmgr descriptor routines for access/transam/generic_xlog.c
  *
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * src/backend/access/rmgrdesc/genericdesc.c

src/backend/access/rmgrdesc/gindesc.c

@@ -3,7 +3,7 @@
  * gindesc.c
  *	  rmgr descriptor routines for access/transam/gin/ginxlog.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/gistdesc.c

@@ -3,7 +3,7 @@
  * gistdesc.c
  *	  rmgr descriptor routines for access/gist/gistxlog.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/hashdesc.c

@@ -3,7 +3,7 @@
  * hashdesc.c
  *	  rmgr descriptor routines for access/hash/hash.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/heapdesc.c

@@ -3,7 +3,7 @@
  * heapdesc.c
  *	  rmgr descriptor routines for access/heap/heapam.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/logicalmsgdesc.c

@@ -3,7 +3,7 @@
  * logicalmsgdesc.c
  *	  rmgr descriptor routines for replication/logical/message.c
  *
- * Portions Copyright (c) 2015-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 2015-2020, PostgreSQL Global Development Group
  *
  *
  * IDENTIFICATION

src/backend/access/rmgrdesc/mxactdesc.c

@@ -3,7 +3,7 @@
  * mxactdesc.c
  *	  rmgr descriptor routines for access/transam/multixact.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/nbtdesc.c

@@ -3,7 +3,7 @@
  * nbtdesc.c
  *	  rmgr descriptor routines for access/nbtree/nbtxlog.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/relmapdesc.c

@@ -3,7 +3,7 @@
  * relmapdesc.c
  *	  rmgr descriptor routines for utils/cache/relmapper.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/replorigindesc.c

@@ -3,7 +3,7 @@
  * replorigindesc.c
  *	  rmgr descriptor routines for replication/logical/origin.c
  *
- * Portions Copyright (c) 2015-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 2015-2020, PostgreSQL Global Development Group
  *
  *
  * IDENTIFICATION

src/backend/access/rmgrdesc/seqdesc.c

@@ -3,7 +3,7 @@
  * seqdesc.c
  *	  rmgr descriptor routines for commands/sequence.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/smgrdesc.c

@@ -3,7 +3,7 @@
  * smgrdesc.c
  *	  rmgr descriptor routines for catalog/storage.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/spgdesc.c

@@ -3,7 +3,7 @@
  * spgdesc.c
  *	  rmgr descriptor routines for access/spgist/spgxlog.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/standbydesc.c

@@ -3,7 +3,7 @@
  * standbydesc.c
  *	  rmgr descriptor routines for storage/ipc/standby.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/tblspcdesc.c

@@ -3,7 +3,7 @@
  * tblspcdesc.c
  *	  rmgr descriptor routines for commands/tablespace.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/xactdesc.c

@@ -3,7 +3,7 @@
  * xactdesc.c
  *	  rmgr descriptor routines for access/transam/xact.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *

src/backend/access/rmgrdesc/xlogdesc.c

@@ -3,7 +3,7 @@
  * xlogdesc.c
  *	  rmgr descriptor routines for access/transam/xlog.c
  *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *