[PATCH 0/5] Colors for git-add--interactive

There are several changes since the last iteration of the "colors for git-add--interactive" patch set:

- Added parentheses around arguments to all user-defined functions.
- Reading the configuration is done in a more organized, robust, and
cleaner way.
- Fixed bug where color keys could inappropriately match ("colored"
should not match "red", for example).
- Users can now set a particular color key to the empty string, and
this is equivalent to setting it to "normal". (This is the behavior
exhibited by git-diff.)
- Color configuration information is case insensitive.
- Added warnings when color configuration keys contain invalid tokens.
- Refactored a few variables for stylistic reasons.

Issues:

- Does not always properly color the output of git-diff --cc, because
  the diff-coloring regular expressions do not match every diff line.
  I'm not sure that git-add--interactive normally gets used in the same
situations as git-diff --cc. They don't seem to work well, together,
from the little that I tested (without the color patches applied).
There are a few solutions, but I haven't thought of one that's both
reliable and clean. My impression is that diff --cc is called any time
that HEAD has two parents. Is this correct?

Dan