using axis.count AND axis.values breaks

Trying to specify 3 values on the y-axis with defined values.

```
axis: {
y: {
tick: {
count: 3
}
}
}
```

..works perfectly, and displays 3 values determined by the library, however

```
axis: {
y: {
tick: {
count: 3,
values: [1, 10, 20]
}
}
}
```

Doesn't display any values on the y-axis. Also I have a button in the DOM which executes a .load API call:

```
chart.load({
json: json_data_weekly,
keys: {
x: 'date',
value: ['reps', 'lbs']
}
})
```

When you click this, the y-values appear, however they're all at the bottom of the y-axis, not spaced properly.

Demo fiddle: http://jsfiddle.net/fz0r36rw/15/