ISPN-800 Tests

* includes tests for put/get custom objects over HotRod
* tests for DistExec, Map/Reduce, Events/Listeners/, basic ispn config file loading, remote store, leveldb store, transactions over replicated caches, single file store
* there are a few todo things: the tests for remote store are currently disabled as they need an ISPN server to be manually started (so the test is @Ignored for now)
* the tests extend tests in ISPN core and so they had to be adjusted (removed testng assertions, a bit of clean up for some tests)
* contains a couple of small fixes

Note: I had to resolve a problem with split package between ispn core and ispn core tests (they contain same packages and OSGi can't cope with that in a good way). So the resulting integrationtests-osgi archive contains packages from both these jars - it's a union of them. Such a consolidated jar is then used in the tests - installed as a bundle.