build_remake: Build a docker container for a a remake project
In traitecoevo/dockertest: Docker images from R packages for testing

Build a docker container for a a remake project

1 2	build_remake(target = "clean", prepare = TRUE, use_cache = TRUE, machine = NULL)

`target`	Target in remake to run. This becomes the "type" (for `build`) and gets translated into the tagname, which can be remapped via the `names:` field in `dockertest.yml`. The target "clean" is special and will unpack the project but not run any remake target.
`prepare`	Rerun `prepare_remake` before building the image?
`use_cache`	Set to FALSE to skip docker's cache
`machine`	name of docker machine to use