feat(rxPaginate): Updated design

Closes #587

Shout out to @glynnis and @Droogans for their styling and testing work on this
I should clarify with some background here. @jj4th complained (correctly) that trying to navigate to the last page with `last()` on a one-page pagination widget threw an error. This allows you to *attempt* to navigate to the last page when already on the last page.

I can update it to something less confusing...perhaps

```js
it('should allow attempting to navigate to the last page when already on the last page');
```

I think that's better.