Idea: use individual "configs" to manage parsing process

Disclaimer: This issue is just a starting point for some ideas i got after working with PDFParser in the last couple of days. So for now, please don't expect anything from it besides some discussion. If someone wants to create PR's based on this, you are welcome.

Issue: There are scenarios in which you need a certain "config" when parsing a PDF. E.g. the PDF requires certain settings or has features, which PDFParser can't handle but you wanna get the most out of it.

Here some use cases which might fit:

• https://github.com/smalot/pdfparser/issues/259: @nickano asks about making PDFObject's $font_space value configurable from outside.
• https://github.com/smalot/pdfparser/issues/294: define your own threshold for a variable to keep \n in parsed text.
• https://github.com/smalot/pdfparser/pull/87#issuecomment-638621328, its about how to separate table cell content after it was parsed. In some cases it won't matter, in some it does.

Related areas:

• parsing process
  • certain thresholds, variable values
  • don't run certain functions (e.g. maybe they crash for a certain file cause features are not supported)
  • ...
• data enrichment afterwards
  • format table content
  • handle attachments or pictures
  • ...

Implementation sketch: Use a config object which gets passed to the parser. Its values will be passed to certain functions along the parsing process to override default values or do activate/deactivate PDFParser features/methods.

Would that be helpful? What do you think?

Start by reviewing the PDFParser parsing process and PDFObject values such as font_space, along with the related issues and pull request discussion linked in the description. Clarify which thresholds, feature toggles, and post-processing behaviors belong in the proposed config object; done requires an agreed design before implementation.