Mini-Patch: a few tweaks

I made a few small tweaks to the game based on data collected from the prior update.

• Changed the Kills Per Second achievement "Total Carnage!" to have a requirement of 30 Kps to reflect recent changes in difficulty.
  
  
• Added support for 1280 x 1024 Monitor resolution as requested in the discussion forum. If you have a resolution you would like to see supported, feel free to just ask by making a post about it in the community discussion.
  
  
• Slightly tweaked some values on weapons to make the steps of each tier more balanced and appropriate.
  
  
• Fixed a graphical bug.
  
  
• Lowered the range on basic zombie attacks by about 30%.
  

-Loren Lemcke