Additionally update the version detection back to 10.5 and forward to 14.
Fill some parts with code from TenFourFox when changes are not obvious.
Using gcc 7 from MacPorts, the gcc 4.8 TenFourFox used is too old.
Don't use GNU as on MacPPC it is too old.
Fix struct/class sizes by limiting bool size.
Brian Smith
8cffdc299f