First 32-,64-bit Linux and 64-bit macOS Release

This release includes full 64-bit support and optional Boehm-Demers-Weiser Garbage Collector.
Now compiles, runs and self-compiles on i386/i686, x86_64, armhf and aarch64 architectures on Linux, and x86_64 on macOS.
Socket transput bug squashed.
Additional sample programs from Glyn Webster.

Initial Release

This release builds on Sian Mountbatten's v1.15. (Release 1.20 chosen as a 1.19 at one time existed, no longer to be found). First new version to compile, run and self-compile on i386, x86_64, armhf and aarch64 architectures.