Removed few files under DynamoWatch3D that are no longer used
Integrated Pan, Orbit and Fit View into contextual menus
Implemented menu for Watch3D to include Pan, Rotate and Zoom
Removed unused "ContextMenuOpening" handlers
Hide Pan/Rotate/Zoom menu options for Watch3D node
Restored "Dynamo.Nodes.Watch3D.SetupCustomUIElements" method
Bound "IsChecked" of "Pan" menu item to "DynamoViewModel.IsPanning"
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse

Conflicts:
	src/DynamoCore/UI/Views/WorkspaceView.xaml
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse
Sync'ed pan/rotate button states while switching workspaces
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Glimpse
Merge pull request #1866 from Benglin/Glimpse

View contextual menu enhancements