The fileinfo tests didn't work on BigSur because of some path and binary changes.
Also, the embeddedPlist method didn't work on fat binaries, of which there are now
many, because of M1 machines. I think we didn't notice this before because we pull
the embedded plist from the first arch listed in the headers dict which generally
seemed to pick x86_64 first but with the arm64/arm64e option being added
that now appears first.
Also fixed some errors handling 32-bit segment/sections and added a test for this.
Add helper to make declaring unit tests easier
Add unit_tests test_suite containing all unit tests
Fix reload rule
Update to workspace-relative header locations that were missed before
