Last version of Swift tempurl MW allow HEAD request
even if PUT or GET are not allowed. This patch
tests that feature.
Related Swift commit: d18b6d8d5d6ca8c0adf3b98b488042c49394a072
This patch also provides some code refactoring to the
middleware.
Change-Id: I33a3f73cf61a0c044428f885154feccb93c672ac