ENH: xlsx template generator

Summary

Allows to create XLSX templates

Focus

Test Environment

unit test (including one for all dimr schemas which is to be removed)

Check List for the Author

Please, prepare your MR for a review. Be sure to write a summary and a focus and create gitlab comments for the reviewer. They should guide the reviewer through the changes, explain your changes and also point out open questions. For further good practices have a look at our review guidelines

• All automated tests pass
• Reference related issues
• Up-to-date CHANGELOG.md (or not necessary)
• Up-to-date JSON schema (or not necessary)
• Appropriate user and developer documentation (or not necessary)
  • How do I use the software? Assume "stupid" users.
  • How do I develop or debug the software? Assume novice developers.
• Annotations in code (Gitlab comments)
  • Intent of new code
  • Problems with old code
  • Why this implementation?

Check List for the Reviewer

• I understand the intent of this MR
• All automated tests pass
• Up-to-date CHANGELOG.md (or not necessary)
• Appropriate user and developer documentation (or not necessary)
• The test environment setup works and the intended behavior is reproducible in the test environment
• In-code documentation and comments are up-to-date.
• Check: Are there specifications? Are they satisfied?

For further good practices have a look at our review guidelines.

src/doc/table-json-conversion/specs.md

@@ -125,8 +125,8 @@ Dieser Eintrag würde in einem XLSX Blatt mit dem folgenden Inhalt abgebildet:
 |-------------------|--------------|
 | www.indiscale.com | Math;Physics |
 
-Die Listenelemente werden separiert von ``;`` in die Zelle geschrieben.  Wenn die Elemente den
-Separator ``;`` enthalten, dann wird dieser mit einem ``\`` escaped.
+Die Listenelemente werden separiert von `;` in die Zelle geschrieben.  Wenn die Elemente den
+Separator `;` enthalten, dann wird dieser mit einem `\\` escaped.
 
 ### d. Properties, die Listen mit Referenzen enthalten ###