[stack-v2] cant fetch or save collection/models without any server

[misstick]

When adding a new contact with newContactModal window : views are not updated because realtime doenst works. Same issue when fetching contacts when application starts.

See add contact use case : https://github.com/misstick/cozy-contacts/blob/d1228c0e0561824cc7fb12e025fbde2b55ac900b/app/models/contact.coffee#L121

Here is realtime adapter : https://github.com/cozy/cozy-contacts/blob/master/client/vendor/cozy-realtime-adapter-1.0.1.js#L44