refactor(ripple): adds support for non-fixed tabs

Closes #825.
Closes #460.
1. Using `matchMedia`:

```js
default: return $window.matchMedia($mdConstant.MEDIA.sm).matches;
```

--
2. Using `$mdMedia` (should be made standalone):

```js
default: return $mdMedia('sm');
```

--
BTW, this should be `$window` instead of `window` in any case ;)