Separate the post-related endpoints

Fixes #348

git-svn-id: http://gsoc.svn.wordpress.org/2013/rmccue/trunk@2206 f69abe3c-2ee2-4550-9a6d-17bd458115be
Use the correct variable in getPostStatuses()

git-svn-id: http://gsoc.svn.wordpress.org/2013/rmccue/trunk@2207 f69abe3c-2ee2-4550-9a6d-17bd458115be