Keybindings in ASE-GUI

It was seen in !465 (merged) that keybinds may be different in tkinter depending on the host system, we should implement some sort of system to rebind keys and be able to see a default binding. I am not sure what the best solution is for this, but maybe some sort of ASE_CONFIG=~/.aserc. I think this may have existed previous as some sort of color contrast option if I recall.

Once we have a method of setting keybinds, users can configure things how they please and hotkey some common UI elements etc that they use. This would also make it so people could hotswap these configs when they are on different machines for using mouse vs trackpad etc. I personally find it very difficult to do things such as right click and drag on my touchpad for example.