This allows other classes to make use of these as well.
Includes a git describe and git toplevel function and functions
to get info for git remotes.
(From OE-Core rev: a04a084b6e513d15cb57ee103c6d6215ce1c75b9)
Signed-off-by: Jermain Horsman <jermain.horsman@nedap.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>