[FEATURE REQUEST] Add bounding box in available-assets

[edwinvandenbelt]

Is your feature request related to a problem? Please describe.

It makes the 'available-assets' endpoint more convenient to use.

Urgency

Major, since most apps use bounding boxes to retrieve assets on a map.

Describe the solution you'd like

Add bounding box fields as arguments on the available-assets endpoint

Possible Implementation

    - name: northEast
      in: query
      description: "optional: bounding box northEast (lat+lon) parameter to limit the results. (See Google Maps LatLngBounds)"
      required: false
      example: northEast=10.12400,51.123123
      schema: 
        type: string
    - name: southWest
      in: query
      description: "optional: bounding box southWest (lat+lon) parameter to limit the result. (See Google Maps LatLngBounds"
      example: southWest=10.12400,51.123123
      required: false
      schema:
        type: string