Config generator: Tile brain area with points

It would be great if we could generate a uniform grid of points over a defined set of brain area. e.g.

```
tileArea('areas',{'VISp'},'pointSpacingInMM',0.5,'side','bilateral')
tileArea('areas',{'VISp'},'pointSpacingInMM',0.5,'side','left')
```

Etc. Can generate points over multiple areas with the cell array. 