Pype-cli

- Fix open formatting and Makefile issues
- Add documentation how to show benchmark information

- Add load time benchmarking using `PYPE_BENCHMARK_INIT=1` as trigger variable
- Replace make script with Makefile
- Replace Travis CI with GitHub actions
- Upgrade build environment

- Complete `pype <plugin> --open-pype <pype>`

- Functionality

- Store configurations in a ~/.pype folder instead of separate files
- Add logging capabilities that are saved in configuration file
- Remove mechanism that resolves plugins relative to configuration file (too complex)
- Disallow re-registering of plugin with same name
- Autocomplete pype names on `--delete-pype` option for each plugin
- Autocomplete aliases on `pype --aliases-unregister`
- Autocomplete plugins on `pype pype.config plugin-unregister`
- Flip option name for `pype --register-alias` and `pype --unregister-alias`

- Development

- Make pype .venv-aware to support system-independent development
- Fix bash-setup for venv

- Code improvements

- Remove facading of config handler in core

- Add [short aliases](pype/__init__.py) for run_interactive and run_and_get_output

- Breaking changes

- Remove unused code in util package
- Introduce pype-cli [import facade](pype/__init__.py) to be able to only import pype

- Code improvements

- Add support for Python 3.8
- Better catch bad JSON configuration file
- Heavily extended integration tests
- Fix a handful of errors in CLI-documentation
- Remove obsolete package imports

- Build process

- Remove tox.ini since it is not used
- Fix command line linter

- Documentation

- Add GIF to README for better documentation
- Add example script in 'basics' plugin that is 100% independent from pype-cli
- Document that pypes are not bound to be used in pype-cli
- Extend documentation of example pypes
- Reference click in documentation to highlight heavy usage
- Reference templates in example documentation