Update gems
Define routes

* add Devise helpers to tests so simulating logged in users is simpler
Add constraining conditional validations to Post

* if the url is empty, the description must not be
* vice versa
Enable self-posting by omitting the URL

* if a Post is missing an url, the partial will route to PostsControllers show
Permit updating only Information Cone description

Closes #11
Merge branch 'routing' into development