CO2 Fixes and Improvements - v0.7.0.23

CO2 generated from human workers / visitors has been fixed, output ratio was incorrect, but main issue was missed the scaling of co2 percentage of air to 0-100%, for display. May still need some balancing here (items that use CO2), but now in the right ball park.

Have also added in a latest news popup on the main menu, so you can see these notes for latest changes in-game.

Patch notes:-

• Latest steam news shown on main menu if English language.
  
• Improve: CO2 production varies depending on humans activity.
  
• Improve: Human CO2 wear helmet level, now based on location co2 level, not ship average.
  
• Fix: Human CO2 output rate increased.
  
• Fix: CO2% level of air, needs to be scaled to 0-100% for habitat display bar / text and alarm check.
  

Nick