Unretiner Pull Request

Hey, I made some changes that I find useful personally. Some of it's just preference, but feel free to pull it.

Changes:
I merged in another fork's changes that disabled the save location prompt (now auto-saves in same folder as file). I changed it so it will convert an -ipadhd image to an -hd image and also a regular image. And tweaked the UI text in the background to make it more descriptive.