amount should be included in render

Currently you'll have to _calculate_ the axis before you can render

This is done by using `amount`

```
vis.gt( 5 ).amount().render();
```

Amount should be implied when you try to render so you don't have that constant extra step. 

A flag like `_amountSetup` that's set when `amount` is executed and reset when a new query method is created will make sure that render isn't using outdated axis. 
