ODLPrincipal extends Principal

ODLPrincipal extends Principal

JAX-RS SecurityContext returns ODLPrincipal when method getPrincipal() is called on SecurityContext.
Method getPrincipal() is returning object of type Principal.
Now we currently cannot cast this object to ODLPrincipal as ClassCastException is thrown,
that makes this completely unusable when using SecurityContext.
Principal.getName() is not providing enough information as it just returns toString() by default.

Signed-off-by: Peter Puškár <ppuskar@frinx.io>
Change-Id: Id17d3b6859732a61de9be48a7b46775c13de6f27
(cherry picked from commit 671e909aed32e3522139e98c0a73e850e0717a7b)