The file commit.c got quite large, but it does not have to be: the
code concerning pretty printing is pretty well contained. In fact,
this commit just splits it off into pretty.c, leaving commit.c with
just 672 lines.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>