The default length for sha1 abbreviations in git is 7.
A '#num' at the beginning of the commit message is now
recognised, a ':#num' as well, etc.: a '#num' anywhere
is now converted to a link.
Signed-off-by: Ferry Huberts <ferry.huberts@pelagic.nl>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>