FEATURE: Add a purge command that removes all mods from the game folder

[dyoung522]

Purge Command

Sometimes the mods we have installed get out of sync with what our database thinks is installed. Or, we may want to remove all mods from the game entirely. To that end, being able to "purge" any existing mods would be helpful.

We should add a "purge" command that essentially resets the game directory back to the way it was before any mods were added (essentially "disabling" all mods).

Additionally, adding a "--purge" flag to the redeploy command would be helpful too. It would simply call the purge routine prior to doing the redeploy.

[dyoung522]

Note that some games have files already installed in the same directory as our mods, so we cannot simply remove all files within the directory. We need to only delete the mod files we've created.