Add support for sorting in natural sort order

See merge request !32

Bumps version in 2020.1

support n-fold cartesian products

Set use_late_start_logging=False if stdin is None

azure-pipeline.yml: Fix argument to prepare-and-run-pylint.sh

Decode stderr in prefork

See merge request !31

py_codegen: Fix deprecated use of imp module.

See merge request !30

Also, this changes an error message to use an '%r' format string for
reporting the bytecode version magic, to avoid printing unreadable
characters.

Tools for memory usage debugging

See merge request !29

EOCRecorder: pretty print formatting

See merge request !28

ProcessLogger: avoid spawning threads in noninteractive environments...

See merge request !27

ProcessLogger: avoid spawning threads in noninteractive environments (https://github.com/firedrakeproject/firedrake/issues/1422)

Improve pdict error printing (closes #6 on gitlab)

Closes #6

See merge request !26