changed name of a custom event 'group:posItDropped' to 'group:postItAdded'
PostItGroupView's COLLECTION gets updated when a postIt is dropped
alter event triggers to pass a group ID and a post ID for drop handling to and from the postIt groups
adjusted to handle and pass back the group ID and postIt ID that is being handled when a post is dropped on a group
removed global used for debugging
tweaked the .render() on the PostItGroupView to empty the root element before populating
the MainBoard.allPostsModels  COLLECTION listens for the custom event 'group:broadcastingPostIt' and removes the associated model from it's domain
focus is set when the header is clicked on the a PostItGroup DOM object
the header attribute is updated on blur from the header of a PostItGroup DOM object
the position attribute is updated on dragstop when a PostItGroup DOM node is moved
REFACTOR: mainly moved some member functions around for readability
added allGroupViews object to track all group views and prevent memory leaks later on
can now delete PostItGroups
updated PostItView to clear its collection before contiuniing the closing sequence to prevent memory leaks