[PATCH 0 of 9 phases] Phase command

[Pierre-Yves David]

The main point of this series is the implementation of the phases command
discussed last week.

This series also to the phase template keyword to prepare the appearance of
phase name in the UI.


This series must be applied before the yesterday one. The whole set of
changeset may be pull from my phase enabled repository:

hg pull http://hg-dev.octopoid.net/hgwebdir.cgi/mercurial/ -r a84c0f8890a4