[#4] Added URI mapping & extended example file

[airnst]

Tickets

[#4]

Justification

See ticket

Code changes

XSLT file:

• Add new variables for icon URI and access URI
• Test for variable occurrence and add if true
  • In case of the access URI, check if file format .zip is specified in it. If so, add schema:contentUrl and schema:encodingFormat to schema:DataDownload in schema:distribution. If not, assign access URI to the unspecific schema:url.