[KIL] Removing most of the old friendship feature (with intention of adding back once bases are established), converting dedicated tables to relations - using the 'follow' model as it seems to be what was in place

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@46910 b456876b-0849-0410-b77d-98878d47e9d5