First pass at multiple Reimport. Mainly so I can reimport EVERYTHING so I can then implement AutoReimport.
Make sure that when you load an image you get the path and the last mod time.
Check to make sure that you're only going to ImageData when searching for Reimport targets
Made it so when you try to reimport an image over another that has different amounts of frames it does not reimport and alerts you.
I can change it to check for frames later but it seems like this would likely be a bad thing to have
(if you have extra frames somewhere in the animation you'll have to re do them, granted you can copy paste but still a big hassle.)