Adds license header
Fixes issue with relationship delete cache invalidation, where recovered commands would fail to
 properly update their node's relationship chain position

RelationshipCommand now on execute will, when recovered, read the current store version and use
 that to invalidate/update the cache.
Removes methods from RelatioshipCommand that were not used and since this change potentially misleading
Fixes some formatting in RelationshipCommand
Enables test case for this issue
Merge pull request #488 from nawroth/hashes

Use jgit to get git describe for the kernel version
Check 3rdparty licenses for all modules.