ISPN-4580 Refactor BaseStoreTest

...and its subclasses

* Remove duplicated code
* replace assert keyword by AssertJUnit methods
* use a mock cache in the stores to test
ISPN-4581 Memory leak when H2 is used

* clear the cache before killing the cache manager
ISPN-4520 JdbcBinaryStoreTest.testLoadAndStoreWithLifespanAndIdle random failures

* Use a custom TimeService to trigger the expiration
ISPN-4527 Make OSGi dependencies "provided"
ISPN-4589 Combiner not being called on the final collector in MapCombineTask
ISPN-4569 Inserting into cache with indexing fails for XA transactions

* Use the BatchModeTransactionManager for the cluster registry cache.
* Suspend ongoing transactions during cluster registry cache operations,
  in case another cache also uses the same TM.
ISPN-4436 Karaf is stucked when running iOSGI integration tests
ISPN-4601 DirectoryLoaderAdaptor computes the auto-chunk factor applying wrong rounding
ISPN-4436 Karaf stucked when running iOSGI integration tests on IBM JDK

Upgrade the PAX EXAM version in the server integration module also.
ISPN-2932 Verify that preloading a read only index in a cache will never hit the cacheloader