Switching core modules to parallel unit test run.

- updated surefire plugin config respectively,
- added tests which verify that common & server module unit tests are run with security manager enabled,
- fixed AsyncCallbackServerTest in server module to be runnable parallelized

Change-Id: I14ab9f90cc1625b43dbad8eeb9ee381c237cdc92
Signed-off-by: Marek Potociar <marek.potociar@oracle.com>