[MERGE] Add __eq__ and __ne__ methods to Repository objects

[Robert Collins]

Robert Collins has voted tweak.
Status is now: Conditionally approved
Comment:
Seems ok, but I would expect that all repositories can be compared with
__class__ and URL.

RemoteRepository isn't using that.

For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C20070806020808.GA23895%40steerpike.home.puzzling.org%3E