Consider inoxie fork and any other rainbow-delimiter addons from forks

[jlr]

I just saw that inoxie/rainbow-delimiters has some interesting code for random color selection for each new paren pair. It might be worth considering it for addition to rainbow-delimiters. I'd want to add a knob to enable/disable it in an emacs init file and add it to the customize interface.

The mode is destined to grow in the future in other ways too - e.g., HTML tag support will probably almost double the size of the thing - so I wouldn't necessarily take issue with adding a new section devoted to this code just to have the option.

Other forks might have interesting stuff too. I'll look at them later. I'll revisit this issue once I have my desktop if you don't want to bother with it.