Customize Splitscreen Tools Dropdown

Section it off with borders and labels, get rid of anything superfluous, pull entries out and turn them into buttons in other sections, whatever is needed.

The easiest way to group options is to use optgroups around the options, but we can only edit the background color and text color of the labels (this changes from browser to browser). It would look something like this:

If we want more control over the look of sectioning the options, we will have to implement something a bit more custom like something seen here
https://tympanus.net/Tutorials/CustomDropDownListStyling/index4.html
or here
https://tympanus.net/codrops/2012/10/04/custom-drop-down-list-styling/
or some hacky things by directly manipulating the here
http://stackoverflow.com/questions/899148/html-select-option-separator

Once a design is decided on, we will know whether or not we need a more custom solution.