ISPN-4232 HotRod client cannot be installed in Karaf due to missing dependency on infinispan-core

Make infinispan-commons a standalone bundle.
ISPN-4234 OSGi core bundle - missing javax.security.* dependency
ISPN-3894 - SingleFileStore can optimize space usage by coalescing adjacent free entry blocks.
Fix failing junit test for SingleFileStoreStressTest as per findings by Dan Berindei
ISPN-3894 SingleFileStore can optimize space usage by coalescing adjacent free entry blocks

* Extract method for existing entry allocation
* More threads in SingleFileStoreStressTest
* Log messages update
ISPN-800 Tests for library mode

* also formatting changes in core/pom.xml
ISPN-800 The osgi test bundle should export the test packages as they might contain classes which need to be loaded by ispn.
ISPN-4097 Add SKIP_CACHE_LOAD flag for Hot Rod
ISPN-3838 L1 entry added by ST when already invalidated

* Removed L1OnRehash as it is broken with a concurrent modification
fixed compilation issue
ISPN-4241 Distexec cannot clone tasks for distributed executions in Karaf

Changed the OSGi headers for infinispan-commons to include DynamicImport-Package=* as the marshaller needs to be able to load classes from client bundles.
ISPN-4261 Clean up Karaf's features files
ISPN-4160 Do not allow the state transfer chunk size to be <= 0