~/.bin/rt: Support the gh: shortcut (for my own repos).

.bin/rt

		rt_PROG="git"
	elif [ -d "$1/.hg" ]; then
		rt_PROG="hg"
	elif [ `echo $1 | grep -E "(git|hub|repo.or.cz)"` ]; then
	elif [ `echo $1 | grep -E "(git|hub|gh|repo.or.cz)"` ]; then
		rt_PROG="git"
	elif [ `echo $1 | grep -E "(hg|bitbucket)"` ]; then
		rt_PROG="hg"