Have the ATTACH command do URI interpretation in the same way as sqlite3_open() and sqlite3_open_v2() do.

FossilOrigin-Name: 68240e75e87a54cde93352b0ec364d34365a8170

src/btree.h

@@ -42,6 +42,7 @@ typedef struct BtShared BtShared;
 
 
 int sqlite3BtreeOpen(
+  sqlite3_vfs *pVfs,       /* VFS to use with this b-tree */
   const char *zFilename,   /* Name of database file to open */
   sqlite3 *db,             /* Associated database connection */
   Btree **ppBtree,         /* Return open Btree* here */