Fix: MAGN-683 Switching tab eventually causes crash in undo
Fix for Dynamo Crashing when node preview is being mouse-overed (MAGN-497).
Fixed Hotkey for controlling background preview.

Adding a new property that take note of both boolean WatchEscapeIsDown and CanNavigateBackground for the hit test of the "Watch3DView".
Removed preview from nodes that are not suppose to have preview.
Merge pull request #730 from l2obin/HotkeyFixesBranch

Fixed Hotkey for controlling background preview.
Merge pull request #731 from SkyApple/RemovingPreviewFromSpecificNodes_ChocoButterUI

Removed preview from nodes that are not suppose to have preview.
Add transform basis x,y, and z.
Updates to NodeDumper.
Don't put spaces before units symbols. It kills the regex.
Merge branch 'master' into ChocoButterUI
Changed code to fast exit.
Merge branch 'master' into MAGN683
Added IsDisconnected property to reflect state of ViewModel.
Add curve-plane intersection.
Add line by start point direction and length.
Add plane from reference plane.
Add transform origin node.
Bail out of viz manager update if controller has been nulled.
Renamed "dynScriptEditWindow" class/files to "ScriptEditWindow"
1. Made "DynamoViewModel.ExecuteCommand" method public (accessible from DynamoPython.dll)
2. Made "RecordableCommand" and all its derived classes public (accessible from DynamoPython.dll)