Native support for programming language library installers

[atheurer]

Instead of using 'manual' method, have workshop understand various installers like pip, cpan, node, etc. The user will list packages in a similar way as is done for yum, dnf, and apt. This way workshop can probe for package versions and generate a more accurate md5sum, and packages within the installer (like pip) can be consolidated across multiple requirement.json files.

[atheurer]

Also support being able to run the different 'installers' at the same time to shorten the time to build a container. For example, allow the 'dnf' installer to run while the 'nodejs' and 'cpan' installer are also running. Fork a process for each of these once the container is active and wait for all to finish.

[atheurer]

Note that supporting the above will probably require certain distro packages are installed first (like node and cpan), then the other installers will be able to work, then these installers can run while the rest if the distro packages are being installed.