Make duplicate handling smarter

On a slightly different note @patrick, I am also using the fileMove feature on some of what I am doing, and I found one strange case where it does things a little unexpected.

Duplicate handling, if you turn off the overwrite duplicates, and it finds a duplicate, it appends an _1 to the end of the filename, however some of the files my users upload already use that same system, so if the base filename is already image_36.jpg, and it finds a duplicate, then instead of doing image_36_1.jpg it just replaces the current _36 and produces this image_1.jpg

Sorry I know this should possibly be a secondary bug report however it’s part of my same image procedure so it makes sense to me, lol. Teo is going to beat me.