Improve GUI for editing variables, refactor for deployment

The variable editing panel has been improved, being able to live edit entries without removing them from the list. The possible entries are now dynamically generated depending on the selected stimulus.

Lots of underlying changes have been made to protocol loading and saving, and other changes to enable app deployment. Opticka can be fully deployed using the MATLAB compiler (only tested on macOS so far, but final target is Linux).

Full Changelog: V2.05...V2.06