Option to set Vibrancy?

**Issue**: Cannot modify default vibrancy

**Reproduce**: 

1. Add the following to `~/.hyper.js`:
```
hyperTransparentDynamic: {
    alpha: 0.5,
    vibrancy: 0
  }
```
2. Reload Hyper

3. Note that there is no effect to Hyper's vibrancy

**Expected Result**: Vibrancy should be disabled