Ensure /apps API old and new formats can run in same WIT

[stooke]

This PR addresses issue #1867.

Various implementation files, directories, function and type names are renamed so that the JSON-API breaking change can co-exist with the old API.
After the UI has been updated (and deployed all the way to production) to use the new JSON-API endpoints (which are not yet merged into WIT/master), then this code can be deleted in a future PR.

[fabric8cd]

@stooke snapshot fabric8-wit image is available for testing. docker pull docker.io/fabric8/fabric8-wit:SNAPSHOT-PR-1868-1

[xcoulon]

PR looks safe: just renaming types.

[codecov-io]

Codecov Report

Merging #1868 into master will not change coverage.
The diff coverage is 39.13%.

@@           Coverage Diff           @@
##           master    #1868   +/-   ##
=======================================
  Coverage   61.37%   61.37%           
=======================================
  Files         139      139           
  Lines       13138    13138           
=======================================
  Hits         8064     8064           
  Misses       4354     4354           
  Partials      720      720

Impacted Files	Coverage Δ
controller/apps_osioclient.go	0% <0%> (ø)	⬆️
controller/apps.go	0% <0%> (ø)	⬆️
kubernetesV1/apps_kubeclient.go	22.77% <39.13%> (ø)
kubernetesV1/apps_metrics.go	54.38% <69.23%> (ø)

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