Colors — PSolTrix Steam update #956471

As already indicated in the last update-post the main improvement in this update is that there new color palettes. There are now ten predefined color palettes, where I tried my best to pick colors that look nice and varied. The colors in the menu, UI and background are changed, too. In hindsight I should have done this a lot earlier, given how much it influences the appearance of the game. However, my programmer-brain told me that choosing nice looking colors isn't important and for some reason I was stupid enough to listen to my brain. Besides the colors there are only a few changes: The color transitions smoothly from tile to border. Minor tweaking of parameters for background animation while playing. Text "MIRROR" in Dotris scene is rendered with one consistent color, now. Audio level of sound and music is correctly loaded at startup of game. With these changes PSolTrix reached versio...