- Add ARCGIS_CABLE_URL, ARCGIS_LANDING_POINT_URL, ARCGIS_CABLE_LANDING_RELATION_URL to config
- Use @property to read URL from settings in collectors
- URLs can now be configured via environment variables
- Add ArcGISLandingPointCollector for FeatureServer/1 (landing points)
- Add ArcGISCableLandingRelationCollector for FeatureServer/3 (cable-landing relations)
- Register new collectors in __init__.py
- Fix earth cables.js with cable_id grouping for highlight