[PATCH 1 of 3] checkcopies: rename 'ca' to 'base'

[Kevin Bullock]

> On Oct 9, 2016, at 09:18, Pierre-Yves David <pierre-yves.david at ens-lyon.org> wrote:
> 
> # HG changeset patch
> # User Pierre-Yves David <pierre-yves.david at ens-lyon.org>
> # Date 1475944722 -7200
> #      Sat Oct 08 18:38:42 2016 +0200
> # Node ID c06cb63082bf1111571fb6fc24bac2e23feefe00
> # Parent  2c8ec8c2ddfeb2d229b81eb5b11e3639fb34b0a0
> # EXP-Topic checkcopies
> checkcopies: rename 'ca' to 'base'
> 
> This variable was name after the common ancestor. It is actually the merge
> base that might differ from the common ancestor in the graft case. We rename the
> variable before a larger refactoring to clarify the situation.

One nit with this one: you also renamed `ma` to `mb` and didn't mention it in the description. Accepting anyway.

pacem in terris / мир / शान्ति / ‎‫سَلاَم‬ / 平和
Kevin R. Bullock