[FEATURE] Add customizable shortcuts

[OctoSheep]

Add shortcuts to quickly switch between monitoring modes.

Samsung phones have system level automation programs, but not as powerful as Tasker, can't send intents, but support shortcuts, so that I can enable Move Mode when I connect to my car's bluetooth to accurately record tracks, and use Significant Change Mode for the rest of the moments to conserve power.

Also, most launchers seem to only support 4 shortcuts, so adding on all modes is impossible, so there needs to be customization.