Improve Rhizome HTTP RESTful interface

Tighten up switch statements on bundle and payload status enums (no
default labels)

Rename some recently added enum entries

Return bundle status and payload status in HTTP responses

Add test for failing to decrypt a foreign encrypted bundle payload,
fix bug that caused an assertion failure

Add tests for fetching a non-existent manifest and fetching bundles
whose payload blob is not in the store
Improve MeshMS HTTP RESTful interface

Provide "meshms_status_message" in returned JSON status content
UNFINISHED Rhizome Java API: get decrypted payload