Filter preset hotkeys

Essentially, give every filter (outline, brightness contrast, etc) the ability to save the current chosen settings as a hotkey. Pressing the hotkey would use the filter with those settings, without bringing up the window. This could be used to instantly:

-Outline outside with a specific color.
-Darken a color by a set amount. (tapping to darken or lighten)
-Increase the size of the canvas by a % (If it had % option)
-Quickly switch to a specific indexed mode.

Along with any uses that come up in the future.