Preview value color RGB, HEX, HSL.

[PeterJones]

@tauniaxd ,

I have added the ability to do rgba(0,127,127,0.05)-type colors to the on-demand script at
https://github.com/pryrt/nppStuff/blob/main/pythonScripts/nppCommunity/21xxx/21044-ColorizeHtmlCssColors.py

If you prefer full underline, then change lines 24 and 26 of the script to use INDICATORSTYLE.PLAIN instead of INDICATORSTYLE.DASH