Expand Refnum Palette to include Synchronization, Event, DVR reference primitives

[smmarlow]

There is a long standing omission in the refnum palette of the synchronization and event refnums primitives. The new and popular DVR ref should also be added.  My example here shows these oft used reference controls at the top of the palette, where I think they should be. While I don't have the rendezvous in my example, it should probably be added as well, even though I don't personally use it that often. In summary, we shouldn't have to do the "create control>cut>paste" shuffle to get the notifier/queue/semaphore/rendezvous/event/data value references.  Sorry if this is already posted.  I searched on refnum palette and didn't see it.

[smmarlow]

14.5 years later, and it's still "New".  This thing is almost the same age as my youngest child, and he's a sophomore in high school.