Ensure that LRA uses the features provided by ArjunaCore

The narayana implementation of LRA does not follow some of the expectations of ArjunaCore:

1. Rename Transaction to LongRunningAction and extend BasicAction (it doesn't need anything from TwoPhaseCoordinator or AtomicAction) and make sure the type name matches the usual convention (ie it should follow the type hierarchy)
2. Do not override BasicAction#end
3. Remove the confusing comment in LRARecord#value()
4. Do not duplicate functionality of BasicAction#Current()
5. Do not duplicate StateManager.get_uid()

There are two more changes that I will raise separate JIRAs for (and link them to this one):

6. Don't use RecordType.USER_DEF_FIRST0 for LRA participants

7. Use the support in ArjunaCore for managing nested LRAs.