Add sample text search dictionary templates and parsers, to replace the

hard-to-maintain textual examples currently in the SGML docs.  From
Sergey Karpov.

contrib/dict_xsyn/expected/dict_xsyn.out

@@ -0,0 +1,22 @@
+--
+-- first, define the datatype.  Turn off echoing so that expected file
+-- does not depend on contents of this file.
+--
+SET client_min_messages = warning;
+\set ECHO none
+RESET client_min_messages;
+--configuration
+ALTER TEXT SEARCH DICTIONARY xsyn (RULES='xsyn_sample', KEEPORIG=false);
+--lexize
+SELECT ts_lexize('xsyn', 'supernova');
+   ts_lexize    
+----------------
+ {sn,sne,1987a}
+(1 row)
+
+SELECT ts_lexize('xsyn', 'grb');
+ ts_lexize 
+-----------
+ 
+(1 row)
+