curl example on ifcOWL page fails when copied + suggestion for RDF access via content negotiation

Great that bSDD supports RDF!

I noticed a small issue while testing the `curl` command from https://technical.buildingsmart.org/standards/ifc/ifc-formats/ifcowl/:
```
curl -X 'GET'
'https://api.bsdd.buildingsmart.org/api/Class/v1?Uri=https%3A%2F%2Fidentifier.buildingsmart.org%2Furi%2Fbuildingsmart%2Fifc%2F4.3%2Fclass%2FIfcWall'
-H 'accept: text/turtle'
```

Copy/pasting this command into a shell does not work because the line breaks are not escaped. This version works:
```
curl -X 'GET' \
'https://api.bsdd.buildingsmart.org/api/Class/v1?Uri=https%3A%2F%2Fidentifier.buildingsmart.org%2Furi%2Fbuildingsmart%2Fifc%2F4.3%2Fclass%2FIfcWall' \
-H 'accept: text/turtle'
```

Another simplification would be to let `curl` handle the URL encoding:
```
curl -G \
--data-urlencode "Uri=https://identifier.buildingsmart.org/uri/buildingsmart/ifc/4.3/class/IfcWall" \
-H "accept: text/turtle" \
https://api.bsdd.buildingsmart.org/api/Class/v1
```

Finally, according to Linked Data principles, an even simpler pattern would be if the identifier URI supported content negotiation (similar to how it already returns `text/html`), e.g.:
```
curl -H "Accept: text/turtle" \
https://identifier.buildingsmart.org/uri/buildingsmart/ifc/4.3/class/IfcWall
```

If the identifier URI supported RDF representations via content negotiation, the RDF would be much easier to consume for Linked Data applications.

Review the ifcOWL page at technical.buildingsmart.org/standards/ifc/ifc-formats/ and reproduce the shown curl command in a shell. Correct the copied command so its line breaks work, then check whether the content-negotiation suggestion is within this website's scope. Done means the example runs as presented and the RDF access request has a documented resolution.

Written by the indexing model from the issue text.