Implement -hash for proper behavior in collections.
Implement -hash for proper behavior in collections.

Signed-off-by: Geoff Garside <c3918f39022407dee6a0056ceca9b1aa80e8e4ce@geoffgarside.co.uk>
geoffgarside/cocoagit,geoffgarside/cocoagit,schacon/cocoagit,schacon/cocoagit