Partial update support (JsonPatch and JsonMergePatch)

- onPatch and JsonMergePatch for KV and Events
- Event Update (with conditional)
- Event Purge (with conditional)
- Get individual event
- Deprecate .put for create, in favor of a new .create
- Improved error handling
- Some perf tweaks (ie rawValue is lazily created)
Fix serialization warnings
Merge pull request #64 from orchestrate-io/jde-partial-updates

Partial Updates