getbundle: support of listkeys argument when bundle2 is used
A new ``listkeys`` is supported by getbundle. It is a list of namespaces whose
content should be included in the bundle.
An appropriate entry has been added to the wireproto map of getbundle arguments
and a new bundle2 capability is advertised.
There are still no codes that request such parts in core mercurial.
% creating repo
% add and commit
C test.py
% change
M test.py