pgsql: Found another small glitch in tsearch API: the two versions of

Log Message:
-----------
Found another small glitch in tsearch API: the two versions of ts_lexize()
are really redundant, since we invented a regdictionary alias type.
We can have just one function, declared as taking regdictionary, and
it will handle both behaviors. Noted while working on documentation.

Modified Files:
--------------
pgsql/src/backend/tsearch:
dict.c (r1.1 -> r1.2)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/dict.c?r1=1.1&r2=1.2)
pgsql/src/include/catalog:
catversion.h (r1.433 -> r1.434)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/catversion.h?r1=1.433&r2=1.434)
pg_proc.h (r1.475 -> r1.476)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_proc.h?r1=1.475&r2=1.476)
pgsql/src/include/tsearch:
ts_utils.h (r1.4 -> r1.5)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/tsearch/ts_utils.h?r1=1.4&r2=1.5)