Fixed bug in NotifyUserOfFatalExceptionAndExit did not show the exception dialog for InvalidOperationExceptions.

Changed exception dialog to copy some extra information to clipboard, and handle the exception when the clipboard is busy.
Added robustness to ExceptionDialog to allow it to copy the exception text to clipboard even if it was spun up on an MTA thread.
Moved BehaviorOption from Main to Pony
Moved some shared state out of Main into more suitable areas.

Removed some no-op code in the DesktopPonyAnimator Update method.
Improved speed of selecting ponies in the editor by suspending some costly grid layout during refresh and added some minimal threading to improve speed and UI responsiveness.
Tweaked PonyEditorAnimator to perform a single draw before pausing and hiding the viewer, thus allowing the buffer to be cleared before switching ponies and preventing a flash of the old pony when animation restarts.
Removed the SaveDialog class and replaced with some MessageBox calls instead.