* Added callbacks to one shot modifier changes
* Altered signature of callback functions
* Reordered the callback methods, shortened brief documentation
* Added One Shot Modifier callback documentation
* First attempt at unit tests
* Revert "First attempt at unit tests"
This reverts commit 5ec21a782202c0d74cf21cb852bd319f0c8b4842.
* Simplified oneshot function implementations
* Made clear_oneshot_locked_mods to be conform action_util.h, adhering to the (void) signature
* Made used datatypes for oneshot mods consistently unsigned integers
* Corrected callback to call clear callback when clear_oneshot_locked_mods is invoked
* Simplified oneshot equals statements
* Corrected return type and signature of get and set oneshot locked mods
* Consolidated one shot callbacks, added initial layer callback version
* Fixed non-updating one shot layer variable after timeout or other clear, added code comments
* Added better one shot key docs