Included relationships between devices and features of interest

Closes #7

See merge request stf/stf-566/saref4watr!1

Closes #7.

Closes #6.

Closes #5.

Closes #4.

Closes #3.

Closes #2.

Plus, a couple of labels have been fixed.

The range of s4city:hasCalculationPeriod should be time:TemporalDuration instead of time:TemporalEntity.

Changed time:Duration to time:TemporalDuration, which is more appropriate since it allows different representations of the duration.

Added the representation of Points and Polygons from GeoSPARQL. This makes redundant the use of the WGS84 ontology, so it is removed.
Closes #1.

Removed the Pesticides instance. On the one hand, pesticides can be both chemical and microbial. On the other hand, it is out of scope to categorize chemical compounds according to their intended use (e.g., pesticide, fertilizer, etc.).