* Add pointers in the main doc to api-ref and releasenotes pages
* Add publish-stx-api-ref job
* Add search at bottom of api-ref and relnotes pages to trigger the jobs
* Add openstackdocstheme installation into requirements file
Change-Id: I11db7e584f3e16f1fd0517a5c0059bdc2d448399
Signed-off-by: Abraham Arce <abraham.arce.moreno@intel.com>