#95 vic should update window size

[Lloyd Lim]

If a vic window is set to a relative size (eg--Actual
Size), then vic should update the size of the window
when the size of the transmitted video changes.

Previously, we never had to worry about this because
all the old sizes were fixed sizes (eg--CIF). Now that
we have settings like Actual Size, we'll have to adjust
the window size.