Improve templates and add references in guides

See description of DOC-101
Added multipple conf.py files to test themes and multiple versions
Created initial structure for references in developer architecture guide and release notes

Change-Id: I7affcd1cb0258bef7cebe357a938080abe419693
Issue-ID: DOC-101
Signed-off-by: Rich Bennett <rb2745@att.com>
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 35f9168..fa752e6 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -4,6 +4,7 @@
 docutils
 setuptools
 six
+sphinx_rtd_theme
 sphinxcontrib-httpdomain
 sphinxcontrib-blockdiag
 sphinxcontrib-seqdiag