XD-329: Field Value Counter REST implementation.

* Merged FVCRepo and FVCService into one
* Added FVC REST exposition and client
* Added MVC tests for FVC and Counter controllers
XD-330 REST Gauge value retrieval

Added GaugesController and MVC integration test. Refactored
GaugeRepository and removed GaugeService.
XD-554 Plugin Refactoring

Separate module context refresh() and start() to allow
post refresh/pre start configuration.

XD-554 Set up Channel Registry in Post Processing

Remove ChannelRegistrar and register channels during
post processing.

XD-554 Polishing (PR Comments)

Added ChannelRegistrationTests to verify the input and output
channels are correctly registered.

Ran it to verify it would have picked up the first PR comment.

XD-554 More Polish

Fix references to AbstractPlugin.setPostProcessContextPaths()
XD-479 Add Conversion to Channel Registries

XD-479 Add NoOpRedisSerializer

Fix up adapters to not use toString() if payload is already byte[]
and the valueSerializer is a NoOpSerializer.

Clone the SI publishing adapter to do the same.

Still doesn't do any real conversion, just to/from String and byte[] (TODO).

XD-479 Add Inbound and Outbound Conversions

- port @dturanski 's JsonRedisSerializer, removing Redis and
    renaming to TypedJsonMapper

- outbound conversion passes byte[] without change and uses the
    TypedJsonMapper for other payloads. The local transport
    performs no outbound conversion.

- inbound conversion uses the TypedJsonMapper to get back to the
    original object; if the sink doesn't support the type, attempt
    to use the conversion service to convert to a supported type.

- Add a boolean property (default true) to the LocalChannelRegistry
    that controls whether any conversion is attempted.

Add tests