Refuse

- Added Python 3.8 support
- Dropped Python 3.4 support
- FIX: Critical bug in error handling, see 26 and 27.
- Improved library structure.

- Removed Python-2-compatibility code
- Improved documentation, especially contribution guidelines
- Added development infrastructure for determining current FUSE version (contribution)

- FIX: `README.md` was not rendered properly on [PyPI](https://pypi.python.org/pypi/refuse).

The following changes were made based on state of `fusepy` as of 2019-05-04.

- FEATURE: OpenBSD support for high level API from [pull request 125 against `fusepy`](https://github.com/fusepy/fusepy/pull/125) was merged.
- FEATURE: Added support for `UTIME_OMIT` and `UTIME_NOW` to high level API. Enable it by adding an `flag_utime_omit_ok` property to your `refuse.high.Operations` sub-class and set it to `1` (integer).
- New Python project structure: [`src` folder](https://blog.ionelmc.ro/2014/05/25/python-packaging/), just a single top-level module named `refuse`
- Modernized `setup.py`, dropping support for Python 2 and `setuptools` < 30.0
- Examples declared legacy