Add functionality to exclude any test using the current exclude mechanism

Currently only tests extending QpidTestCase can be excluded using the exclude file mechanism employed by the java ant tests.
There are several test cases that does not need to be run with every profile, but they cannot be excluded since they don't extend QpidTestCase.

Ex. SlowConsumerDetectionConfigurationTest is exclusively for the java broker and does not need to be run when using the cpp test profiles.

On the other hand you cannot make them extend QpidTestCase as by default this class will start a broker.
Therefore it would be nice if we have a simple class that implements the exclusion and then the current QpidTestCase to extend it.

I think it's best if we have a simple class called QpidTestCase that implements the exclude functionality (and perhaps capture the test output as well) and then rename the current QpidTestCase to QpidBrokerTestCase and make it extend QpidTestCase.

This will allow us to easily extend any JUnit test case from the profiles.