* Add theme and plot thickness options
* Cleanup
* Fixed themes, and made it so the plot colors are updated when the theme is changed
* I think supporting themes beyond dark, light, and black is unecessary for the time being.
* recall theme from settings before instantiating plot
* Check for null setting
* committing to merge
* Fix
* Cleanup
* Cleanup
* Fix from comments. Thank you kamkie!
* Fixing last UI bugs
* Fix windowed plot not theming on relaunch, change theme, show plot
