Create .dateParser()

Create parser generator method called `.dateParser()`

```javascript
var parser = Globalize( "en" ).dateParser({ date: "short" });

[ "1/1/14", "2/1/14" ].map(function( x ) {
   return parser( x );
});

// [ Wed Jan 01 2014 00:00:00 GMT-0200 (BRST),
//   Sat Feb 01 2014 00:00:00 GMT-0200 (BRST) ]

```

Ref #294
Fixes #298

- [x] Implement
- [x] Docs
- [x] Tests