Settable number of actions per step

[dmasad]

At the moment, all matched actions occur every step, in the order the nouns were matched. In some cases, it would be good to only fire a subset of possible actions (for example, if there are N characters who can meet each other, we may want only one pair to meet per step rather than N x (N-1) pairwise interactions). If the order in which actions occur matters, it would be useful to have this randomizable as well.

[dmasad]

I've started testing a solution with a settable number of actions per step, where available actions are added to an array and then chosen at random:
https://github.com/dmasad/seaduck/blob/n.actions/seaduck.js#L171
The problem so far is that when the actions per step is low, the state doesn't always change between steps, leading to a premature _end.