[MERGE] improved lp:/// URL support for the Launchpad plugin

[Robert Collins]

Robert Collins has voted approve.
Status is now: Approved
Comment:
I'm happy that John has done a detailed review.

I'd like to suggest that there should be some api that bzr exposes that 
the launchpad developers can use to see if they break bzr's lp support - 
now that we need this RPC we'll want to be sure lp doesn't skew from it 
without warning. That can be a separate patch I think, but it should be 
done.

For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3Ca7e835d40711051145t4dc7feb5v7bf4601651d2aab4%40mail.gmail.com%3E