Adds support for using custom dockerfiles to pre-install image
renderer plugins.
Updates docs for docker and image rendering.
Fixes#20241
Co-Authored-By: Leonard Gram <leo@xlson.com>
* build: Install musl cross compilers as part of build Docker image
* build: Build also musl packages in scripts/build/build.sh
* scripts/build/build-all.sh: Build musl Linux targets
* build: Upgrade build-container to 1.2.11
* build.go: De-duplicate code
* build: Base Docker images on musl binaries
* switch docker image to alpine base
* Docker: switch packaging image to alpine
* use alpine image for build containers
* switch base images in build script
* only try to set up phantomjs on x86_64, reduce number of layers
* phantomjs binary is bundled with grafana
* speed up circleci build
* convert build.sh to functions and add args for different build types
* add yarn cache
* add build latest to packaging step
* fast build should not try to tag non-amd builds
* remove signing step for prs-and-branches
