[added] Hash support

Allow to define hash mixed routes.
Examples:

      Router.define({
        'index': '/',
        'hello': '/users/#/hello/:name',
        'articles':'/#/articles/:id'
      });
[added] Optionnal use of hash
Update README.md
Update README.md
Update router.js
Update router.js
Update router.js
Merge pull request #3 from mpipet/master

[added] Optional hashchange support