1) Made options more practical with enums (new options can now be adding simply by adding an entry to the Option enum)
2) Fixed combo box highlighting
3) Renamed Options class to OptionsHandler
4) Moved Main.optionsHandler to OptionsHandler class (now OptionsHandler.instance)
5) Began exponent delimiter option implementation (it's simple but I did all of the other stuff first and felt like it would be good to commit it)