Phantom - Custom poster border/background zag colors

[Toletheus]

Request - add options to control the poster border and background zag colors as follows:

1. Choose color for inner border (default now is white)
2. Choose color for outer poster border (default now is black)
3. Choose color for selected/highlighted game poster (not featured, but would make identifying selected item easier)
4. Choose color of background zig-zag pattern

The addition of this functionality would make the add-on fully customizable for a larger range of uses.

Thanks for your contributions!

[EMERALD0874]

Not planned atm but if anyone wanted to contribute this, I'd be happy to review a PR