Refactoring

git-svn-id: https://plugins.svn.wordpress.org/ml-slider/trunk@888310 b8457f37-d9ea-0310-8a92-e5e31aec5664
Increment version to 2.8-beta

git-svn-id: https://plugins.svn.wordpress.org/ml-slider/trunk@888311 b8457f37-d9ea-0310-8a92-e5e31aec5664