Blender Git Loki

Steam Release: Script creation of Steam build files

Script tool for automation of Steam build files for tasks like {T77348}

This script automates creation of the Steam files: download of the archives,
extraction of the archives, preparation of the build scripts (VDF files), actual
building of the Steam game files.

Requirements
============

* MacOS machine - Tested on Catalina 10.15.6. Extracting contents from the DMG
archive did not work Windows nor on Linux using 7-zip. All DMG archives tested
failed to be extracted. As such only MacOS is known to work.
* Steam SDK downloaded from SteamWorks - The `steamcmd` is used to generate the
Steam game files. The path to the `steamcmd` is what is actually needed.
* SteamWorks credentials - Needed to log in using `steamcmd`.
* Login to SteamWorks with the `steamcmd` from the command-line at least once -
Needded to ensure the user is properly logged in. On a new machine the user
will have to go through two-factor authentication.
* App ID and Depot IDs - Needed to create the VDF files.
* Python 3.x - 3.7 was tested.
* Base URL - for downloading the archives.

Reviewed By: Jeroen Bakker

Differential Revision: https://developer.blender.org/D8429