Changes

tsk28 Adds resource to get user stories
Adds resource to get the user stories. The user must be logged in, and
only could get his stories. If someone try to obtains other user's 
stories, or to get anything without being logged, it will receive an
error. Modifies sql and dataset files to adapt them to the new resource,
and adds the 'role' field in the database and in the User entity. 
Modifies web configuration files to turn on the http authentication.