Remove duplicated code from test cases where custom modules are needed

When writing some integration tests for the PicketLink subsystem, I've noticed that there is no utility class or API to make easier create and remove custom modules from the modules directory.

There are a few tests with this requirement, and most of them are replicating code.

After discussing with kkhan1@redhat.com, he suggested to open this JIRA to review those test cases and make them use a reusable component to work with custom modules.

I've already wrote a class that I think can satisfy all test cases requiring a custom module.
See https://github.com/pedroigor/wildfly/blob/WFLY-2733/testsuite/integration/basic/src/test/java/org/jboss/as/test/integration/picketlink/util/TestModule.java.
Usage example: https://github.com/pedroigor/wildfly/blob/WFLY-2733/testsuite/integration/basic/src/test/java/org/jboss/as/test/integration/picketlink/idm/JPAEMFFromModuleBasedPartitionManagerTestCase.java#L81