Add a bootstrap css based theme to groups portal, and match the design
elements and layout of new openstack.org site. This patch will not
enable the theme by default, just add the bootstrap module and the
openstack subtheme. The subtheme is based on the sass version of
bootstrap with a bundle compass support.
Change-Id: Iae976151e87d4d2edd6e913a5aea16d9c13dc051
6cbed3be20