Addin should store IDE window meta-data

[abegel]

In order to support a user playing back the stored X,Y data, the addin should be storing:

1. VS window position (x, y, width, height)
2. Editor window position (x, y, width, height)
3. Editor viewport (x, y, width, height) (that's for recording the scroll position within the editor)

[abegel]

Please record this information every time it may change, e.g. when someone moves the window or editor or scrolls the editor window.