Log Message:
-----------
Minor editorial improvements to txid functions' documentation: put back
some text that got dropped, improve markup, improve descriptions of
snapshot components.
Modified Files:
--------------
pgsql/doc/src/sgml:
func.sgml (r1.409 -> r1.410)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/func.sgml?r1=1.409&r2=1.410)