Additonal functions in the saved game menu

[Former user]

Unless I'm missing something, there doesn't appear to be a way to delete saved games from the save/load menu.

It would also be nice when naming or renaming saved games to rapidly delete characters automatically when holding the backspace key, like a standard text editor. It's somewhat annoying having to do it one character at a time.

[Braden Obrzut]

Added delete function in change set cd66430.

I'm going to reject the key repeat request at least for now, since I don't know what I might be doing with the input system in the nearish future and I don't want to scatter more SDL calls around in the mean time if I don't have to.