5.0.0

• Adjust for Mathics3 core 5.0.0 API
• Fixed autobrace and rewritten with Condition from prompt_toolkit.filter
• Add $GroupAutoComplete setting (default True) to disable completing closer group symbol. Feature provided by DUO Labs and Alessandro Piras.
• Remove bindings for the right brackets
• For prompt-toolkit and GNU Readline users, we allow a user input binding file in CONFIGDIR/inputrc (e.g. ~/.config/mathicsscript/inputrc).
  You can set the location this file via environment variable MATHICS_INPUTRC
• Handle version-getting timeout better
• Python 3.6 tolerance
• Create code of conduct
• Some code linting