Updated type definitions for handlebars#registerPartials (#27388)
Updated type definitions for handlebars#registerPartials (#27388)

* Updating types for #registerPartial

#registerPartial is a polymorphic function now it accepts a single object making the second param optional.

Excerpt from the implementation:

```js
  registerPartial: function(name, partial) {
    if (toString.call(name) === objectType) {
      extend(this.partials, name);
    } else {
      if (typeof partial === 'undefined') {
        throw new Exception(`Attempting to register a partial called "${name}" as undefined`);
      }
      this.partials[name] = partial;
    }
  },
```

* Updated Handelbars#registerPartials

Removed extra spaces

* Added function overload with typed arguments

Replaced polymorphic argument types for registerPartial function with overloaded function definition

georgemarshall/DefinitelyTyped,borisyankov/DefinitelyTyped,AgentME/DefinitelyTyped,georgemarshall/DefinitelyTyped,AgentME/DefinitelyTyped,borisyankov/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,dsebastien/DefinitelyTyped,AgentME/DefinitelyTyped,dsebastien/DefinitelyTyped,AgentME/DefinitelyTyped,markogresak/DefinitelyTyped,mcliment/DefinitelyTyped,magny/DefinitelyTyped,magny/DefinitelyTyped