Python: improve numbers, add octals, binaries and "breakpoint" keyword

Summary:
BUG: 414996
FIXED-IN: 5.66.0

Changes:

• Improve number detection with underscores. Add binaries and octales. (I took the regular expressions from the TypeScript highlighting file and adapted them to Python).
  
  See: https://www.python.org/dev/peps/pep-0515/

• Add keyword "breakpoint" introduced in Python 3.7: https://www.python.org/dev/peps/pep-0553/

Reviewers: Framework: Syntax Highlighting, dhaumann, cullmann

Reviewed By: Framework: Syntax Highlighting, dhaumann

Subscribers: kwrite-devel, kde-frameworks-devel

Tags: Kate, Frameworks

Differential Revision: https://phabricator.kde.org/D25869