deal with -wall unused code warnings in C.D.P.P.Service.Registry

- remove unused import of InitHandler
- remove usused `reason` fn
- comment out unused/unimplemented `dispatch` fn
- mark _unused arg to `handleUnmonitorReq`
linting; rm unused imports
Merge pull request #84 from BirdseyeSoftware/refactor-remove-unused-warnings

deal with -wall unused code warnings in C.D.P.P.Service.Registry