MWD Highs & Lows

This is a minor update and modification to the script by kisshore19: I updated a few pieces to make it v4 compliant (color. and syminfo. prefixes, etc), inserted the passed variables on the functions, and modified a few items per my preference (line style, removed the infinity offset, added transp). Very minor updates, the work is all credit to kisshore19. I wanted to be able to update which previous days/weeks were shown so bringing it up to date with v4 was the idea.