Clarify collections consistency rules

[dr-shorthair]

See #326 (review)

Provide examples to illustrate each rule

[dr-shorthair]

See examples for the 5 cases here: https://github.com/w3c/sdw-sosa-ssn/tree/328-collections-consistency-rules-examples/ssn/rdf/tests/ObservationCollection

Note that these are all consistent with the matching case.
A full test suite would also include examples which are inconsistent in all ways - which is a lot.

[ldesousa]

The examples look good. The ranges expressed with the Time ontology make it clear.

If you wish to perfect further: the term property in the italics segments can be misinterpreted as actuating properties, instead of datatype/object properties.

[dr-shorthair]

I've folded these into a new Pattern - see preview https://raw.githack.com/w3c/sdw-sosa-ssn/328-collections-consistency-rules-examples/ssn/index.html#ModelCollectionRules