Ribbon menu support

I have updated the ribbon-menu-support branch to the most recent master.  I have also added in the default control templates for most of the Ribbon.  I could not get one for the tooltip.

This will make it easier for people to help in finishing this control.  I commented out the parts of the control template that were already there before I added the default template in case they are needed at some point.

After adding the default templates I noticed that the menu no longer displays when you click the button.  I have not had time to figure out why.  If you comment out ```<ResourceDictionary Source="RibbonApplicationMenu.xaml" />``` in Styles\Ribbon\Styles.xaml the menu will work fine.  Someone just needs to figure out what in RibbonApplicationMenu.xaml needs to be changed to make the menu appear.

Also after adding the default template for RibbonTab I noticed there are now scroll buttons on the tab.  We need to style these so I left it there.  However, at some point we will need to figure out what in RibbonTab.xaml makes the scroll button appear when there is not enough content to scroll.

There are a lot of templates to style.  Hopefully people will check out this updated branch and start to work on styling the controls that make up the ribbon.