Log Message:
-----------
Give a more specific error message for "you can't do that" error cases
in plpgsql, particularly trying to begin/end/rollback a transaction.
Modified Files:
--------------
pgsql-server/src/pl/plpgsql/src:
pl_exec.c (r1.114 -> r1.115)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/pl/plpgsql/src/pl_exec.c.diff?r1=1.114&r2=1.115)