[FEATURE]Quality Options for Skin Database

[ghost]

Since hd skins etc are a thing now, this should be expanded. Let people choose in which quality they want to download the skin. Allow the Uploader to upload different images for one skin. Maybe add a min/max quality option for the pack, with a disclaimer towards potential long loading screens.

Maybe this is also a good point to get some standard sizes?
For example:

• standard definition is 256x128
• good definition 512x256 (x2)
• high definition 1024x512 (x4)