Move some components to shell scripts and stop writing shell scripts for temporary use
Two things for this:
The files we use to put in stubs during bootstrapping (such as fake start-stop-daemon) should just be files on the host rather than written out each time.
Some things we do are probably better described as shell scripts. Infact, we may want to look into just calculating a list of shell commands to build a distribution filesystem or image and then go from there, instead of running them inside appliancekit.