[FEATURE] Support for multiple custom/rainbow skins from mods

[JKohlman]

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• iOS app (its already being development)

Currently BetterCrewLink only recognizes the last custom/rainbow skin (RGBA 0, 0, 0, 255) in the skins table if multiple are added. It would be beneficial if support was added for multiple of these types of skins to allow mod makers to add more compatible content.