Adds and installs the Forum Engine
Adds rspec support and ensures that account signup works.

Ensures thru the passing test, that the application is using the
subscribem engine, and that thru that engine a user can signup and
create an account with a subdomain.
Adds tests and ensures users can sign in and access their subdomain.
Adds tests to ensure that the engine's scoping feature works.

Ensures thru the addition of tests and configuration changes that the
scoping feature implemented on the subscribem engine is working as
intended on the hosted forums app.