Icon placeholders

[John.d.h]

Since the engine already generates placeholders for missing models and textures, what about icons?  It would make testing a bit easier, as (AFAIK) icons are absolutely required, and they're one of the last things I make.  At least sounds can be commented out.

Here's one you can use.

[Omega]

Good idea, and seconded, since I ended up having to make placeholder icons early on in Military (and I still dislike my current icons, but can't think of any cool ideas, plus, I suck at icons). Though, to make it easier to play test, I propose that there's a few different icons that are based on the command (ie: attack commands without an icon would have a white "A" on a black background).