Code-base debt erasure: Draft

[kjohn-msft]

This is a draft PR covering more than 30 issues/bugs that have existed as debt in the code-base (some for years).

The code has also been reorganized for consistent coding practices, higher reliability in execution, easier maintainability and faster troubleshooting.

This description will be enhanced when the code is ready for review. Portions of this may go in as separate reviews.

[codecov]

Codecov Report

Merging #224 (173c522) into master (b50ef62) will decrease coverage by 53.11%.
The diff coverage is 22.78%.

@@             Coverage Diff             @@
##           master     #224       +/-   ##
===========================================
- Coverage   90.39%   37.28%   -53.11%     
===========================================
  Files          90       70       -20     
  Lines       14810    11304     -3506     
===========================================
- Hits        13387     4215     -9172     
- Misses       1423     7089     +5666     

Flag	Coverage Δ
python27	37.28% <22.78%> (-53.11%)	⬇️
python39	37.28% <22.78%> (-53.11%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
src/core/src/bootstrap/Constants.py	98.77% <100.00%> (+0.11%)	⬆️
src/core/src/external_dependencies/distro.py	29.08% <ø> (-24.84%)	⬇️
src/core/tests/Test_Container.py	23.52% <ø> (-70.59%)	⬇️
src/core/tests/Test_LifecycleManagerAzure.py	4.16% <ø> (-90.63%)	⬇️
src/core/tests/Test_PackageFilter.py	3.70% <ø> (-95.38%)	⬇️
src/core/tests/Test_Stopwatch.py	2.70% <ø> (-96.42%)	⬇️
src/core/tests/Test_UbuntuProClient.py	2.56% <ø> (-90.85%)	⬇️
src/extension/src/Constants.py	98.07% <100.00%> (+0.01%)	⬆️
src/extension/src/ProcessHandler.py	83.84% <100.00%> (ø)
src/extension/src/RuntimeContextHandler.py	72.00% <ø> (ø)
... and 59 more

... and 18 files with indirect coverage changes