Add feature to show multiple colors in the nMonths view cells.

git-svn-id: https://plugins.svn.wordpress.org/cp-multi-view-calendar/trunk@1027870 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added feature to make the calendar work in hidden tabs, so it can calculate the available with for rendering the calendar once the tab has been made visible.

git-svn-id: https://plugins.svn.wordpress.org/cp-multi-view-calendar/trunk@1027871 b8457f37-d9ea-0310-8a92-e5e31aec5664