REQUEST: Include new function ULuaScreenSing_SetScores

[OverzetKaraoke]

For use in custom Party-Mode plugins, I would like to request the LUA function: ScreenSing.SetScores.
Similar to ScreenSing.SetSettings, a table would be used as an argument to push scores from the plugin to the game.

This would make it possible to make old plugins for UltrastarES compatible with USDX.
(https://ultrastar-es.org/foro/viewtopic.php?f=5&t=3718)
Such Party modes include:

• First to reach 1000 points gets 10% deducted from the total score
• Whenever you lead with 500 points, the score of your opponent gets increased by 500 points
• ...

This feature had previously been implemented by someone, but I am unable to find the orginal source for their Usdx.UltrastarES class.