ubic.ping: http-code checks by service name

[berekuk]

ubic.ping supports following urls:

  /ping (self-check)
  /status/port/777 (check by port, return status in body)
  /status/service/foo.bar ( check by name, return status in body)
  /noc/777 (check by name, return status in http code)

This is inconsistent and we need to be able to check status by name and represent result with http code.
Also, none of these are documented (except in tutorials)!