minimize space by choosing optimal libraries, removing source files, etc.,.

[satra]

as an example, the tensorflow docker image is tiny relative to any tensorflow image we may produce with miniconda or some such.

• dynamically linked binaries are going to reduce space for FSL/ANTs/AFNI etc.,. so we need to figure out recipes to build those from source across at least a few OSes
• the additions for the build process itself should not be in a container post build. so i think every build recipe should have a -pre, -build, and -post section to help with cleanup.

just some thoughts here as we try to optimize container sizes, and build steps.