Editor: Multiple editor viewports

This adds the ability to have multiple viewports in the Editor.  I havn't added orthographic camera support so I don't pass my wife's merciless standards but I think this bit is working pretty well.  I tried to be thorough, give it a shot and let me know if there are any problems.

Here is my criticisms:
- From a ux stand point i feel like the borders are hard to grab.
- The code is a bit heavy handed and brute forced.  The only way I could make the code simpler with my knowledge would be to have some sort of observer but there it isn't very easy to do inside of angelscript.

Thanks :heart: :metal:
Chris