Add hotkey support in all windows (including non-program ones)

[lispascal]

Add hotkey support for Push-to-Talk through a JNI (Java Native Interface).

Context:
Currently push-to-talk is only supported inside the config/test window.

Downside to JNI is that the program will lose portability to all platforms but the one the JNI is used for, so try to at least implement for Windows and Mac