refactors get_object_https_url request, adds temp_signed_url method to file class
adapts aws method signatures for temp url generation
refactors create_temp_url method to use the options hash for schemes instead of a parameter
adds object tests for get_http_url, get_https_url
Merge pull request #2206 from anynines/openstack_temp_url_support

Openstack provider: Temp url support for Files