bumping django_openstack_auth version

Dependency for fixing Horizon bug.

Change-Id: Ie8202544fbc227e1b86e18525c19096c498a64b4
Partial-Bug: #1211535
Set python-six minimum version

missing python-six minimum version from the requirements.txt
set the min version to 1.4.1

fixes bug: #1237205

Change-Id: I74b3324aa09412b49ce8eeaba9910ee6852e520a
temporarily cap python-troveclient version

Version 1.0 from the HttpClient perspective is not backward
compatible.  Horizon has trove integration in Havana and
significant rework would be required to fix the compatibility
issues for the Havana release.

This cap would only be for the Havana release.

Partial-bug: #1238121

Change-Id: I52e8ddc4a8f79ec7f358a07d00aabe9c2046b6c7