Merge branch 'dev'

* dev: (38 commits)
  changed readme
  removed schema submodule
  Post Methods Updated
  added missing providers
  removed obsolete dependency
  changed deps of webapp to other modules to runtime
  load guice modules with java.util.ServiceLoader
  Update README.md
  Create README.md
  syntax error checking script
  syntax errors
  measurement creation schema
  GeoJSON reference
  measurement schema
  missing comma
  track schema
  fixed required user fields
  removed groups from user json
  tracks.json
  measurements schema
  ...
Merge branch 'dev'

* dev:
  fixed guice runtime errors (merely a workaround; see #21)
Merge branch 'dev'

* dev:
  seperated de/encoders from providers (fixes #21)
Merge branch 'dev'

* dev:
  encode measurements directly in tracks and lists  (fixes #22)
Merge branch 'dev'

* dev:
  GeoJSON encoding of track/measurements/measurement
made all read access open for everybody