* Bump Go to 1.17, refactor build/x86_64 Dockerfile to make better use of multi-stage
* Bump to 1.17 from 1.16
* Bump packr version, provide needed legacy env var
* Add apple silicon support, fix macos build chain
* Update unused travis ci
* Run in same container
* Add cross compile targets to makefile
* Use make targets and existing container
* Cache UI build
* Update cross-compile script
The toolchain is already bundled in the stashapp/compiler image.
Rather than introducing a second one via GH actions standardize on that
one instead.
Also
* Clear up what "Cross Compile" actually does
* Still pull stashapp/compiler separately for easier debugability.