branch --color: change default color selection.

branch --color: change default color selection.

Showing local and remote branches in green and red was simply
overkill, as all we wanted was to make it easy to tell them
apart (local ones can be built on top by committing, but the
remote tracking ones can't).

Use plain coloring for local branches and paint remotes in red.

Signed-off-by: Junio C Hamano <junkio@cox.net>