fix(setup.cfg): use 'find:' to include submodules; other tidying

[mwtoews]

This should fix the missing modules using the special find: directive described here. Also remove attr:, which only works for version, and remove sdist option, as it's probably not used here. I don't see the licence files, but this shouldn't matter.

The best way to build/check the package is using python -m build (which may required python -m pip install build, if not already there. And better from PyPI than conda for this tool, as it's written by PyPI).

Also update the installation documentation for presumably the stable version from PyPI.

[codecov[bot]]

Codecov Report

Merging #102 (0c98d70) into master (154d139) will decrease coverage by 50.889%. The diff coverage is n/a.

:exclamation: Current head 0c98d70 differs from pull request most recent head 5955cab. Consider uploading reports for the commit 5955cab to get more accurate results

@@              Coverage Diff               @@
##            master      #102        +/-   ##
==============================================
- Coverage   65.919%   15.030%   -50.890%     
==============================================
Files           16        16                
Lines         4105      4105                
==============================================
- Hits          2706       617      -2089     
- Misses        1399      3488      +2089     

Impacted Files	Coverage Δ
pymake/utils/_compiler_language_files.py	8.333% <0.000%> (-87.500%)	:arrow_down:
pymake/pymake_base.py	2.732% <0.000%> (-84.290%)	:arrow_down:
pymake/utils/_usgs_src_update.py	6.303% <0.000%> (-81.662%)	:arrow_down:
pymake/utils/_compiler_switches.py	3.587% <0.000%> (-77.355%)	:arrow_down:
pymake/pymake_build_apps.py	7.291% <0.000%> (-75.000%)	:arrow_down:
pymake/utils/_Popen_wrapper.py	17.500% <0.000%> (-72.500%)	:arrow_down:
pymake/utils/_dag.py	9.836% <0.000%> (-72.132%)	:arrow_down:
pymake/plot/dependency_graphs.py	11.627% <0.000%> (-52.326%)	:arrow_down:
pymake/pymake.py	23.364% <0.000%> (-51.714%)	:arrow_down:
pymake/autotest/autotest.py	2.493% <0.000%> (-24.678%)	:arrow_down:
... and 2 more

[jdhughes-usgs]

Thanks for fixing this Mike.