Running the brain demo gets warning every iteration

I get a warning every loop when running the brain demo code:

```
if(this.regression && y.constructor !== Array)
console.log("Warning: a regression net requires an array as training output vector.");
```

This is the basic code from demo/rldemo.html

``` javascript
function start() {
// var brain = new deepqlearn.Brain(num_inputs, num_actions);
var brain = new deepqlearn.Brain(3, 2); // 3 inputs, 2 possible outputs (0,1)
var state = [Math.random(), Math.random(), Math.random()];
for(var k=0;k<10000;k++) {
// var action = brain.forward(array_with_num_inputs_numbers);
var action = brain.forward(state); // returns index of chosen action
var reward = action === 0 ? 1.0 : 0.0;
brain.backward(reward); // <-- learning magic happens here
state[Math.floor(Math.random()*3)] += Math.random()*2-0.5;
}
brain.epsilon_test_time = 0.0; // don't make any more random choices
brain.learning = false;
// get an optimal action from the learned policy
var action = brain.forward([.9, .3, .1]);
console.log(action);
}
```