Auto Build Unity Package File

I think it might be beneficial to auto-build a Unity Package in order to easily import this package into other projects.

NOTE: We also have to make sure that all of our scene specific prefabs and other things are not included in the packages.

This may be helpful:

We could probably use this with a pre-push hook in git to make sure a new Package File is built every time we push a new version.

src: https://docs.unity3d.com/412/Documentation/Manual/CommandLineArguments.html

Helpful: https://forum.unity.com/threads/exportpackage-command-line-in-unity-3-5-7.210480/