CAS-1362: The computed principal is no returned through service ticket validation

In fact, things are pretty "simple" :
- authentications computed by resolvers are stored in the chained authentications at the TGT level
- primary authentication are computed for service ticket validation response (depending on the service).

Thus the ```casServiceValidationSuccess.jsp``` should use the ```primaryAuthentication``` to return the computed principal and attributes, but should rely on the ```chainedAuthentications``` to get all proxies.

By the way, it's worth noticing : 
- there were already some tests on the primary authentication returned
- the CAS protocol 2.0 successful validation page uses the primary authentication.

I add tests to confirm some behaviours (```ignoreAttribute``` and ```anonymousAccess``` properties).