major reconstruction in mongoose main file - fixed flawed connection to the database. - General   * added more internal usage of Promises.   * added update flags, so validation doesn't get passed - Service Objects   * fixed adding service objects, for existing gateways, new gateways and no gateways   * added same gateway creation logic to updating gateways.   * fixed returning of all service objects for gateway   * fixed returning of all service objects for userID - Gateways   * fixed removing gateways but keeping service objects and updating their gateway information - SensorData   * added validation before saving and getting sensor data   * fixed getting sensor data   * fixed removing sensor data. here no validator is called
major reconstruction in mongoose main file
- fixed flawed connection to the database.
- General
  * added more internal usage of Promises.
  * added update flags, so validation doesn't get passed
- Service Objects
  * fixed adding service objects, for existing gateways, new gateways and no gateways
  * added same gateway creation logic to updating gateways.
  * fixed returning of all service objects for gateway
  * fixed returning of all service objects for userID
- Gateways
  * fixed removing gateways but keeping service objects and updating their gateway information
- SensorData
  * added validation before saving and getting sensor data
  * fixed getting sensor data
  * fixed removing sensor data. here no validator is called

  In general this was way harder than expected and thus took way longer than intended.
  All this is covered under the soon-to-be-commited test-case.

SEDARI/serios