refactor index
added header module initializer
added header module file, start with parent object set to false, and call listHeader method that points to header list controller when the module starts
added header module list controller, initialized the List module and set list controller object nad listHeader method
set headerView variable to get instance of headerView, instantiate new list header and show the header view in the headerRegion
added list view, instantiated List.Header class and extend from marionette ItemView class, set header list template path
added header list template file and markup