Refactored scopes checks

* Added fail fast when scope string is empty (before error was thrown at use time)
* Made `checkSecured` a member of `SecuredInfo`
Merge pull request #1 from bric3/SecuredInfo_refactoring

Refactored scopes checks
use core release version
[maven-release-plugin] prepare release jaxrs-oauth2-0.5
[maven-release-plugin] prepare for next development iteration