"branch -d" can remove more than one branches
"branch -d" can remove more than one branches

Since 03feddd (git-check-ref-format: reject funny ref names, 2005-10-13),
"git branch -d" can take more than one branch names to remove.

The documentation was correct, but the usage string was not.

Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git