Add support for Camelot

[liadmagen]

Add pdf extraction support for Camelot:
https://camelot-py.readthedocs.io/en/master/
To enable also extract the content of tables in PDFs.

This includes:

• ensuring it's easy to install it on different OS
• adding the package to the installation for setup
• implementing the usage of this package
• changing the ability of choosing which package is used