Currently, log decorations do not indicate which branch is checked out
and whether HEAD is detached.
When branch foo is checked out, change the "HEAD, foo" part of the
decorations to "HEAD -> foo". This serves to indicate both ref
decorations (helped by the spacing) as well as their relationshsip.
As a consequence, "HEAD" without any " -> " denotes a detached HEAD now.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
