Make dice rolls results more informative

After moving to mathjs, all the math that is done is "hidden" to the player. They see their dice roll, and then a message saying what their skill was set to. But no mention of how it arrived at that number without looking up all their character's dynamic stats and doing the math themselves.

It should say something like: !roll perception Perception: {1d20}+Level+Trained = {14}+2+4 = 20