Include posters in Twitter notifications

* Also cleanup Facebook

lib/requests_oauthlib/compliance_fixes/__init__.py

@@ -0,0 +1,7 @@
+from __future__ import absolute_import
+
+from .facebook import facebook_compliance_fix
+from .linkedin import linkedin_compliance_fix
+from .slack import slack_compliance_fix
+from .mailchimp import mailchimp_compliance_fix
+from .weibo import weibo_compliance_fix