Performance improvements and modernization
This release covers the following changes:
- Vectorisation of EFD calculation and inverse transform - contributed by @mgb45
- Support for the pyshp 2.x new file IO interface
- Support for pytest 5.3.5 and redesign of tests to cope with these breaking changes
- Updates to the CI pipeline
- Full testing of python 3.7 and 3.8 and dropping testing on python 2.x on Windows
- Highlighting the end of support for python 2.x
- Fixing typos in documentation