[Feature request] Keyboard shortcut support

[wokes]

First of all, great app!

It'd be great if you could define keybinds (preferably system-wide) to perform actions in the app - namely pausing/resetting the timer and skipping.

[jblaszczyk]

there's even a long forgotten key on every ANSI keyboard screaming to be used that way :)

[Splode]

#310 adds support for global shortcuts, which are customizable.