Dice rolls are wrong #1
Description
It doesn't handle spaces in the roll - ,roll 1d1 + 3 is not 4, but ,roll 1d1+4 is.
Moreover, the expression is not handled correctly. https://github.com/MattRead/JibbyBot/blob/master/Plugin/Dice.php#L114
applies the bonus to every die. ,roll 3d1 + 3 should be 6, not 12.