Changes

tsk39 Refactors REST layer and its tests
REST layer base route configuration has been moved out of 'web.xml'
files and onto a new JaxRsActivator class. With this, paths can be
extracted programatically from tests, without the need to hard-code the
different resource paths as Strings. New utils for REST testing have
also been added and existing tests refactored to use them.
Some methods have also been moved from UserResource to EventResource, as
they are mostly related with Events and not with Users.