[PATCH] provide better committer information to commit-tree.c

[PATCH] provide better committer information to commit-tree.c

Here's a small patch to commit-tree.c that does two things:
	- allows the committer email address and name to be overridden
	  by environment variables (if you don't like the environment
	  variable names I've used (COMMIT_AUTHOR_NAME,
	  COMMIT_AUTHOR_EMAIL), feel free to change them.)
	- provide the proper domainname to the author/committer email
	  address (otherwise, my address was only showing up as from the
	  hostname.)

This allows people to set sane values for the commit names and email
addresses, preventing odd, private hostnames and domains from being
exposed to the world.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>