added friendly message when adding someone to conversation that is not part of clique

Ignore-this: 68fbe13c4cad01f417a1d1eaf9427e28

darcs-hash:20141030135540-c21fe-6c00da9970eda831b034e783a7916c3810c2589c
Merge branch 'master' of https://github.com/mempko/firestr