Add _.create method

`_.create` is useful as both a "polyfill" for `Object.create` and a utility for simple prototype inheritance.

Implementation is adapted from Lodash's `_.create` method. I've kept the `baseCreate` function for the usage in the methods @jdalton [mentioned here](https://github.com/jashkenas/underscore/pull/1901#issuecomment-60267844).

```js
function Person(name, occupation) {
  this.name = name;
  this.occupation = occupation;
}

function Developer(name) {
  Person.call(this, name, 'developer');
}

Developer.prototype = _.create(Person.prototype, {
  constructor: Developer
});

var developer = new Developer('Jeremy Ashkenas');
developer instanceof Developer;
// >> true

developer instanceof Person;
// >> true
```

Ref: @jdalton https://github.com/jashkenas/underscore/pull/1901#issuecomment-60267844
My bad got lost in the source

On Sat, Oct 25, 2014 at 9:08 PM, James Kyle <notifications@github.com>
wrote:

> In underscore.js:
>
> > @@ -998,6 +1012,23 @@
> >      return obj;
> >    };
> >
> > +  // Creates an object that inherits from the given prototype object.
> > +  // If additional properties are provided then they will be added to the
> > +  // created object.
> > +  _.create = function(prototype, props) {
>
> It's not already? The closest header above says "Object Functions"
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/jashkenas/underscore/pull/1907/files#r19378463>.
>