Consolidate tar file extraction into one function again

[CommandMC]

This brings back part of the function that was removed before & uses that function everywhere it's applicable
extractFiles can now also be easily extended to support more file types (e.g. .zip)

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Use the following Checklist if you have changed something on the Backend or Frontend:

• Tested the feature and it's working on a current and clean install.
• Tested the main App features and they are still working on a current and clean install. (Login, Install, Play, Uninstall, Move games, etc.)
• Created / Updated Tests (If necessary)
• Created / Updated documentation (If necessary)