Follow the new PTI for document build

For compliance with the Project Testing Interface as described in:
https://governance.openstack.org/tc/reference/project-testing-interface.html

For more details information, please refer to:
http://lists.openstack.org/pipermail/openstack-dev/2017-December/125710.html

Change-Id: I2a7c07767c0f46cebca355e617d5cc58efa5b161

setup.cfg

@@ -37,24 +37,6 @@ data_files =
         diskimage-create/tox.ini
         diskimage-create/version.txt
 
-[build_sphinx]
-all_files = 1
-build-dir = doc/build
-source-dir = doc/source
-warning-is-error = 1
-
-[pbr]
-autodoc_tree_index_modules = False
-autodoc_tree_excludes =
-    setup.py
-    octavia/tests/
-    octavia/db/migration/
-autodoc_index_modules = False
-autodoc_exclude_modules =
-    octavia.tests.*
-    octavia.db.migration.*
-api_doc_dir = contributor/modules
-
 [wheel]
 universal = 1