bug 294 - fixing documentation error - we just added set 2

Conflicts:
	doc/adminguide/addthings.sgml
Fixing documentation according to bug 293.

http://www.slony.info/bugzilla/show_bug.cgi?id=293
Merge branch 'REL_2_0_STABLE' of git://git.postgresql.org/git/slony1-engine into REL_2_0_STABLE