[rbp] Fix non-square pixel display apect ratio and 3D TAB modes correctly

On Pi, we've always treated display pixels as square. This is a little wrong for composite 4:3 displays, and a lot wrong for composite 16:9 displays.
It's also wrong for various hdmi modes with non-square pixels.

The newer API  for tv service, can report display aspect ratio.
(requires newish firmware, but we've already forced that recently)

The newer API also reports if top and bottom 3D modes are supported, and I've added support for that.
Files should contain 3DTAB in the filename, (3DSBS in filename was previously supported).

The newer API can report all the information (e.g. group, mode, 3D support and interlace) from the get current mode call, so we can avoid the hack of replacing the "desktop" resolution with a matching resolution one from the probed list.

Also previously if 1920x1080p and 1920x1080i were supported they would both show up as valid resolutions, but when selected, the progressive version was forced, so the option in the resolutions list was redundant. I now only add interlaced modes to resolution list if they are unique.