This release features a great contribution from the Rails Girls Summer of Code:
The landing page of the webapp can now include a twitter feed to display
news from the provider.

Other than that this is a maintainance and transition release.

* Twitter feed on main page (thanks theaamanda and lilaluca).
* upgrade to rails 4.2
* upgrade to bootstrap 3

Upgrading:

* We now use rails 4's `secret_key_base`. Please make sure to supply it
  in config/config.yml for production environments. If you are using the
  leap platform that will already take care of it.

Deprecations:

* We have not seen any active use of the **billing** functionality.
  So we deprecate it and will probably drop it in one of the next releases.
* We will replace the user facing **help desk** functionality with a single
  sign on mechanism to integrate with other help desk systems.
  We will maintain the endpoint to submit tickets and the ticket management
  in the admin interface. That way it should also be easy to create your own
  ticket submission form.
* We deprecate the ability to **signup and login** directly through the webapp.
  We will remove it in the future for security reasons. Signup and Login should
  only happen through bitmask to prevent password phishing and js injections.

our special error handler for json requests would turn all exceptions
into 500s - removed it. now the rescue_responses can do their thing
again.

We'll only use the master branch for development from now on.

* upgrade to rails 3.2.22.4
* fix ticket url issue

use_database affects all uses of prepare_database - so also the one
in tmp_database. In order to avoid that we do not use_database but
just overwrite the database method itself.

It was causing 404s on initializing the database with db:migrate.
DatabaseMethods rewrite of #database does not call prepare_database
and thus does not create the database when needed.

DatabaseMethod is also quite a bit too much for a model that has
two databases that can be memoized easily. There's no way to have
a separate database instance per record.

We already did the same for other concerns. The way we load models
for couchrest migrations does not work well with concerns in the
model directory as they will be loaded twice.

We saw errors from duplicate loading of LocalEmail and
LoginFormatValidation. The latter resulted in a crash.

In an attempt to ensure all subclasses of Couchrest::Model::Base are
loaded Couchrest::Model::Utils::Migrate requires all files in app/models.
We have an extension that does the same for the engines.

During this process LoginFormatValidation and LocalEmail were autoloaded
when 'identity' was required. Afterwards they were required again.
It looks like rails' autoload mechanism does not play nicely with require.

So to make sure they are not autoloaded first move the concerns and
helper classes into the lib directory and require them explicitly.