Hyperlinked format extension support

This PR should:
- extend the format page generation code to support hyperlinked in displayed format extensions while preserving the index creation logic
- add simple hyperlinks to OME-XML, OME-TIFF and Zeiss CZI as proofs of concepts
- fix a bug in the formats table for formats with no extension
- update the auto-generated format pages with all the changes above (and fix whitespaces)

/cc @melissalinkert