Distinct matching by supported modes and preferred modes

[koiuo]

It should be possible to match not only by supported modes, but also by preferred mode.
Match by preferred mode should have higher score than by supported modes.

mode in match section should be renamed to supports, though mode should be kept valid for compatibility

"match": {
    "DP1": {
        "supports": "1920x1200",
        "prefers": "1920x1200",
        "edid": "1234567890"
    }
}