Fixes #719. Changes the red cross on the health scanner HUD to the same ...

...green cross that's on the medkits.

Before:
![](https://a248.e.akamai.net/camo.github.com/7c2de529e9a9da3b6f255d235c89fdae430b74cd/687474703a2f2f7075752e73682f333875754a2e706e67)

After:
![](http://puu.sh/3scQS.png)