Improve Doxygen description parsing

[silvester747]

The current description parser for Doxygen input has a lot of limitations and bugs. Create a new parser that supports all tags and has better new line handling.

• [x] Support extra content fields like todo, deprecated, since, etc in templates
• [x] Set correct language for code blocks
• [x] Ensure full test coverage
• [x] Write full changelog
• [x] Support tables
• [x] Support ulink
• [x] Support formulas
• [x] Test markdown format
• [x] Update documentation
• [x] Support images
• [x] Clean up