Patch: Respect viewport for various widgets/larger MythTV program description

[Bernhard Geier]

I was always unsatisfied with the very small MythTV program description shown on
the screen when pressing the "OK" button while watching a recording. I made it larger and centered it on the screen.

I also noticed that some widgets, namely mute, ffwd, zoom, clock and
osd, do not respect the viewport settings and also tried to fix this.

I tested this patch with 4:3 and 16:9 PAL and different viewport settings, for
me it works.

viewport_and_mythOSD.diff