merge externals for bw1129 fork

[nerdCopter]

• cherry-picked https://github.com/Plasmatree/PID-Analyzer/pull/33/commits
• cherry-picked https://github.com/Plasmatree/PID-Analyzer/pull/54/commits
• manually commit of Smeat@1527ea5 with originator's authorship

notes only:

• @Smeat & @atomgomba (https://github.com/Smeat/PID-Analyzer/commits/master) have some useful work here, but i did not process any merges of it.
• I feel the community needs a more updated version, and maybe your fork may be the best location. (or maybe Smeat's with your code merged 🤷)