Introduce typedef for handling BAR values
Ensure orphan payloads or manifests are cleaned up
Fix coverage test documentation to reflect changes required to support clang
Ensure directory service tests aren't creating a global routing table
Reinstate rhizome database storage limit

- old / large payloads should be evicted to fit more payloads
- if there isn't enough space, new payloads will not be added
Merge NAF4 MeshMS Java API into development

Currently implements "list conversations" and "list messages"
Include Java tests in 'tests/all' if Java compiler available