[PATCH] Remove total confusion from "git checkout"

[PATCH] Remove total confusion from "git checkout"

The target to check out does not need to be a branch. The _result_ of the
checkout needs to be a branch. Don't confuse the two, and then insult the
user.

Insulting is ok, but I personally get really pissed off is a tool is both
confused and insulting. At least be _correct_ and insulting.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>