#2 Let users upload their own icons

[emi]

Let users upload their own icons. This will need a directory where images will be saved. Each user will have it's own subdir and there will be a common dir, also. Users will be able to upload icons to their directory or to the common one. Icons uploaded or moved to the common directory can't be removed via web (other users may be using this image).

Possibly, there will be the needs of some upload control mechanism to avoid any abuse by users. This will come later. Until then, only servers with responsible users will be allowed!

Also, it's possible to need some image manipulation frontend to be able to resize images that don't fit the size it should. This will come later, too.