Merge macOS compatibility updates from rgov/starter-pack

[alexchandel]

Merge the key macOS compatibility updates from rgov/starter-pack, while reverting the breaking TaskQueue (f004f65 & e38f403) and Unix/POSIX file mode unzipping (1958aac).

Drive-by bugfixes for newlines and for unzipping were recommitted separately (1c84665 & 62f0058).

For now, in the absence of POSIX file mode unzipping, a package builder can properly reextract PyLNP after running main.py with:

rm -rf 'build/Starter Pack Launcher (PyLNP).app'
unzip components/PyLNP_0.13b-OSX.zip -x PyLNP.json -d build  # change to latest zip
mv build/PyLNP.app 'build/Starter Pack Launcher (PyLNP).app'

Of course the final distribution zipping still fails, but that's OK since a macOS distribution will be packaged by some other means anyway (e.g. a dmg).