Merge branch 'master' into svn

git-svn-id: https://plugins.svn.wordpress.org/papercite/trunk@854751 b8457f37-d9ea-0310-8a92-e5e31aec5664
Updated version to 0.5.6

git-svn-id: https://plugins.svn.wordpress.org/papercite/trunk@854755 b8457f37-d9ea-0310-8a92-e5e31aec5664
Stable version is 0.5.6

git-svn-id: https://plugins.svn.wordpress.org/papercite/trunk@854759 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added a Papercite prefix to OSBib/Pear classes to avoid name clashes