Pull Request, which will contain all changes from ODF 1.3 CSD03 to ODF 1.3 CS02 (changes done before review phase)

[svanteschubert]

Started with a single issue and will add fixes incrementally. Flagging this PullRequest therefore as a draft, until it is ready!
NOTE: Using a label as the "draft pull request feature" exists only for GitHub Team & Enterprise ;-)

[svanteschubert]

Please note, I have fixed first the ODT, by using JEdit with archive PlugIn to access, edit and save the content.xml file within the ZIP.
Afterwards, I have been using an unzip batch file to unpack the ODT into the folder.
Therefore, if the change of the unzipped content.xml is correct, so is the ODT :-)

[svanteschubert]

At this stage, decided to better stick to the TC-agreed wording from the former issue:
https://issues.oasis-open.org/browse/OFFICE-3873
Instead of following the wording recently suggested by Patrick:
https://lists.oasis-open.org/archives/office/202010/msg00016.html

[svanteschubert]

Changes made so far:

1. Updated the wording according to https://issues.oasis-open.org/browse/OFFICE-3873
2. Updated IDs of deliverables references in the ODT (exchanged 'CSD03' to 'CS02' and 'CS01' to 'CSD03') 
3. Fixing in part 3 the 'broken' link from 'http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.49.6093' to 'https://ctan.mirror.norbert-ruehl.de/biblio/bibtex/base/btxdoc.pdf'
4. Fixing ODF 1.2 XML manually by removing ODF 1.3 attributes to become valid
5. Fixing missing whitespace after MathML entities in HTML
6. Generated new HTML & PDF documents

[mistmist]

the .owl files need fixing

[svanteschubert]

The final summary of all (non-material) changes:

• Updated the wording according to https://issues.oasis-open.org/browse/OFFICE-3873
• Updated IDs of deliverables references
  • in all file names and added a schema directory for RNG, OWL files
  • in the ODT (exchanged 'Draft 03' to '02', 'CSD03' to 'CS02' and 'CS01' to 'CSD03') 
  • in the RNG/RNG-HTML 
  • in the OWL files 
• Fixing in part 3 the 'broken' link from 'http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.49.6093' to 'https://ctan.mirror.norbert-ruehl.de/biblio/bibtex/base/btxdoc.pdf'
• Fixing ODF 1.2 XML manually by removing ODF 1.3 attributes to become valid ODF 1.2
• Fixing missing whitespace after MathML entities in HTML
• Generated new HTML & PDF documents