+ New method to determine if a username already exist in db.
+ Session is now injected in AbstractBackingBean.
+ Session is produced in Resources.
+ New qualifier session.
+ New Template template_auth.xhtml. It is used for pages which are
within restricted areas. The only difference is at the moment that there
is a logout option in the upper right corner.
+ Registration validates the username. If username is already taken the
user is informed and cant submit the page.
+ Servlet 3.0 Authorisation works well.
+ Form in login.xhtml is a h:form again. j_security_check is out of
date.
+ Added method to HashService which consumes a username and produces a
SHA-256 digest without salt or whatnot.
+ Realm in web.xml was wrong.
+ New constant "REGISTRATION_VALIDATION_VALUE". Preserves if
registration values are valid or not. E.g. when form is submitted and
RegistrationBean is requested again.