[PATCH 0 of 6] Refactor localrepo.commit() to read from changectx

[Patrick Mezard]

Here is a followup of "[PATCH 0 of 5] Support committing without a working
directory" posted the 2008/06/02.

This series focuses on rewriting localrepo.commit() to take a changectx like
object as single argument, and remove all dirstate management code. The second
point is not complete yet because some parts are deeply embedded in commit
code, but the result is good enough so memory contexts can be built and passed
to _commitctx().

I would like to have some feedback about this approach before starting with the
memctx and refactoring convert.

BTW, these changes have the good side effect of failing the commit upon bad
username or date *before* asking for the commit message (or starting the
transaction).