feature: Make attribute watching opt-in

Rather than opt-out. So this:

```
hc-chart-events-load="ctrl.onChartLoad"
hc-watch-series[0]-data="ctrl.chartData"
```

Instead of this:

```
hc-static-chart-events-load="ctrl.onChartLoad"
hc-series[0]-data="ctrl.chartData"
```
docs: Auto-updates are now opt in
feature: Just don't watch anything yet...

This is going to be a bigger headache than I was hoping. We'll circle back to
around later.
chore: Bump for release (v0.2.0)