Make the git prompt (when enabled) show a CHERRY-PICKING indicator
when we are in the middle of a conflicted cherry-pick, analogous
to the existing MERGING and BISECTING flags.
Signed-off-by: Jay Soffian <jaysoffian@gmail.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>