Better dockerRunArgs handling, ensure slug is lowercase, add install parameter

[elijahr]

Some dockerRunArg values would fail, due to improper handling of quotes. This is sidestepped by parsing the arguments into an array using shlex, then passing that array's items as separate N arguments to run-on-arch.sh.

It also seems that the container names must be lower-case, so we ensure the slug() function returns a lower-case string. Some GitHub repositories will have upper-case letters.

Edit: I've also added an install input parameter, which runs as part of docker build. This allows dependency installation to be cached in a docker image layer that persists between builds.

[uraimo]

Thanks!! 2.0.2 tagged!

[elijahr]

Thank you!