Handle simultaneous combos

[dlip]

If you press a combo on the right side eg. j+k to output 'a' at the same time as a combo on the left side eg. d+f to output 'b', the first one wins and you get 'adf' instead of 'ab'.

My use case for this is to improve the implementation of the taipo layout, which uses a lot of combos and treats each side as a one handed keyboard so this type of roll happens quite often. Here are more details on the layout if you are curious https://inkeys.wiki/en/keymaps/taipo