turn on warning-is-error in doc build

sphinx.ext.napoleon is a preprocessor which converts Google style
docstring into ReST style. This is required to avoid sphinx warnings.

warnerrors = True in [pbr] section is no longer needed
in favor of warning-is-error in sphinx.

Change-Id: If4a7adfae5dab3313bb54ad465a75290476b7154

doc/source/conf.py

@@ -22,6 +22,7 @@ sys.path.insert(0, os.path.abspath('../..'))
 extensions = [
     'sphinx.ext.autodoc',
     'sphinx.ext.doctest',
+    'sphinx.ext.napoleon',
     'openstackdocstheme',
 ]
 

setup.cfg

@@ -26,6 +26,7 @@ packages =
 source-dir = doc/source
 build-dir = doc/build
 all_files = 1
+warning-is-error = 1
 
 [upload_sphinx]
 upload-dir = doc/build/html
@@ -34,9 +35,6 @@ upload-dir = doc/build/html
 directory = futurist/locale
 domain = futurist
 
-[pbr]
-warnerrors = True
-
 [wheel]
 universal = 1