Enable Shift and Alt Keys in Menus

[XxMiltenXx]

I request that the Shift and Alt-key get added to menus.

If you have sliders or numfields with low increments (that are actually needed for precision) it can be quite slow to get from the minimum to the maximum and vise versa. The Shift and Alt-key could be used as a multiplier when held, e.g. Shift will be 10x the increments and Alt 100x the increments.

There might be other uses as well, but for now I am requesting it for that reason. Doesn't hurt if it is available in general for all menus.