upgrade theme version

requirements.txt

@@ -1,4 +1,4 @@
 Sphinx==1.8.5
-sphinx-rtd-theme==0.2.4
+sphinx-rtd-theme==0.5.0
 sphinx-autobuild==0.7.1
 transifex-client==0.13.11

source/conf.py

@@ -30,6 +30,7 @@ release = '0.9.10'
 # ones.
 extensions = [
     'sphinx.ext.todo',
+    'sphinx_rtd_theme',
     'sphinx.ext.githubpages'
 ]
 #For internationalization:
@@ -54,7 +55,7 @@ master_doc = 'index'
 #
 # This is also used if you do content translation via gettext catalogs.
 # Usually you set "language" from the command line for these cases.
-language = None
+language = 'en'
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.