JBPM-4449 - Support for Weblogic 12c for kie workbench

Adjustments to make UberFire and Kie workbench to run on Weblogic 12c:
- beans.xml added to uberfire-backend-cdi otherwise it will have incorrect bean manager and thus won't be able to find beans - same thing is required for errai-weld-integration 
- weblogic roles adapter to be able to find roles of authenticated users - same pattern as for WebSphere
- adjustments to async service to make the timeout for termination on shutdown configurable and reduced time by default