sensor schemata
phenomenons schemata
created/modified props for phenomenons and sensors
measurements schema
tracks.json
removed groups from user json
fixed required user fields
track schema
missing comma
measurement schema
GeoJSON reference
measurement creation schema
Merge branch 'master' of https://github.com/car-io/car.io-schema

* 'master' of https://github.com/car-io/car.io-schema:
  fixed syntax errors

Conflicts:
	user.json
syntax errors
syntax error checking script