[VOL-2875] Documentation update

- Updated the main landing page and overview documentation
- Added the lab setup (copied from CORD docs)
- Use forked sphinx-multiversion to publish docs, which allows versions
  to be listed at bottom of sidebar
- Updated logo and favicon, fixed CSS to make logo legible
- Use VERSION file to set the version in the sidebar
- Add more words to dictionary
- removed reload functionality that is nonworking in Sphinx 2.x
- Fixed lint/linkcheck issues

Change-Id: I032e67d76393778fc697944a6d5df9c8cdacbbc4
diff --git a/requirements.txt b/requirements.txt
index 6f4c716..3a3044c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,12 +1,10 @@
-Sphinx~=2.4.3
+Sphinx~=2.4.4
 actdiag~=2.0.0
 blockdiag~=1.5.4
 doc8~=0.8.0
-livereload~=2.6.1
 nwdiag~=2.0.0
 recommonmark~=0.6.0
 seqdiag~=2.0.0
-sphinx-reload~=0.2.0
 sphinx-rtd-theme~=0.4.3
 sphinxcontrib-actdiag~=2.0.0
 sphinxcontrib-blockdiag~=2.0.0
@@ -14,9 +12,6 @@
 sphinxcontrib-openapi~=0.6.0
 sphinxcontrib-seqdiag~=2.0.0
 sphinxcontrib-spelling~=4.3.0
-# using a fork as the main branch is broken in newer sphinx, per:
-# https://github.com/sphinx-contrib/sphinxcontrib-versioning/issues/58
-# also added functionality to support working with other repos
-git+https://github.com/zdw/sphinxcontrib-versioning@0998d870b2791eb6343c98e98d6680c1e727daee
+git+https://github.com/zdw/sphinx-multiversion@ec7c01cdaf2f9241245e84483dfb9bc0d0dffc62
 # sphinx-autoapi~=1.2.1
 # sphinxcontrib-golangdomain==0.2.0.dev0