Update Sphinx and modules versions

- Only build branches, not every point release
- Bump site copyright date
- Remove a few unused sphinx extensions

Change-Id: I96468446f1f85fdff2daf5a9e1e7e8b85b61b378
diff --git a/conf.py b/conf.py
index b40278b..05a442a 100644
--- a/conf.py
+++ b/conf.py
@@ -25,7 +25,7 @@
 # -- Project information -----------------------------------------------------
 
 project = u'VOLTHA Docs'
-copyright = u'2019-2020, VOLTHA Contributors & Open Networking Foundation'
+copyright = u'2019-2021, VOLTHA Contributors & Open Networking Foundation'
 author = u'VOLTHA Contributors'
 
 # The short X.Y version
@@ -53,18 +53,9 @@
     'sphinx.ext.ifconfig',
     'sphinx.ext.mathjax',
     'sphinx.ext.todo',
-    'sphinxcontrib.actdiag',
-    'sphinxcontrib.blockdiag',
-    'sphinxcontrib.nwdiag',
-    'sphinxcontrib.openapi',
-    'sphinxcontrib.packetdiag',
-    'sphinxcontrib.rackdiag',
-    'sphinxcontrib.seqdiag',
     'sphinxcontrib.spelling',
     "sphinx_multiversion",
     "sphinx.ext.intersphinx",
-#    'sphinxcontrib.golangdomain',
-#    'autoapi.extension',
 ]
 
 # API documentation
@@ -88,6 +79,9 @@
     'make prep',
 ]
 
+# don't include tags
+smv_tag_whitelist = None
+
 # inlcude only the branches matching master and voltha-*
 smv_branch_whitelist = r'^(master|voltha-.*)$'