rest things
rest + core changes for measurement
REST REST and more REST
validator / updater for track
license header updates
measurement validator + updater (init)
measurement module added to mongomodule
core + mongo modules updated
rest track
removed collection name for embedded class
added track identifier
added missing exception mappers to provider module
basic tracks provider implementation
fixed get track by id
Merge branch 'datamodel' into event-stream

* datamodel:
  fixed get track by id
  basic tracks provider implementation
  added missing exception mappers to provider module
  added track identifier
  removed collection name for embedded class
  rest track
  core + mongo modules updated
  measurement module added to mongomodule
  measurement validator + updater (init)
  license header updates
  validator / updater for track
  REST REST and more REST
  rest + core changes for measurement
  rest things