Add optional parameter for changed/added/del/unknown files to commands.dodiff
This makes it possible to avoid a call into repo.changes if the details
of what has changed is already known
+ hg clone a b
abort: repository a/.hg not found!
255
+ hg clone http://127.0.0.1:3121/a b
requesting all changes
abort: error: Connection refused
255
+ hg clone a b
abort: repository a/.hg not found!
255
+ hg init
+ hg clone . ../a
abort: destination '../a' already exists
1
+ hg clone a b
abort: repository a/.hg not found!
255
+ hg init
+ hg clone q
abort: destination 'q' already exists