Dynamic key changes

[SimenZhor]

Updated the dynamic key repeater with an extra gear. After a given interval (5 seconds added or subtracted to the interval) the repeater will add whole seconds to the interval instead of 0.1 sec incrementations.

Reasoning behind the change:

I like the idea of a dynamic incrementation, but (at least with the currently set constants) it's not allowed to accelerate for more than 0.6 seconds ( (keyRepeatRateSlow-keyRepeatRateHigh)/keyRepeatRateStep = (500-100)/60 = 6.666 incrementations at 100ms sample rate). For me this felt very slow when navigating the menu, and I expected the incrementations to further accelerate at some point. So I added some sort of hacky code (I personally think the whole incrementation code should be rewritten) to add what I've called a "bonus gear". What this does is to wait for 50 incrementations to be applied (or subtracted), then it will change the incrementations from 0.1 second to 1 second until the up/down button is released. As the current application of your controller has a maximum of 99 seconds I realize this is kind of a special case that won't be used often, but at least to me the buttons feel more natural now.