Logout from external sites

Features:

• Add Remote Logout, using a force flag, e.g. hello( 'facebook' ).logout( { force:true } ) see #18

Provides AMD support

Amd support means hello.js can be used in module loaders thusly

 require(['path/hello'], function(hello){
         hello.init(...);// etc...
 });

• Fix bug #41
• Adds feature #40
• Updates #39

Adding me/contacts, fixes #37 and #36

• Moves old google:me/friends contacts endpoint to google:me/contacts.
• Changes google:me/friends to use Google+ circles
• Add windows:me/contacts
• Changes "windows:me/friends" to remove empty email property

Support added for Safari Private Browsing and IE protected mode

Adds a fallback from localStorage to sessionStorage else cookie for session data.

Safari Fix Release

Address a bizarre behaviour whereby URI fragments are lost in Safari, that includes the access_token and therefore breaks authorization of subsequent requests.