Early Access v0.21.0 ComicCon update

Join the community, and come help us improving translations for City Game Studio

• Improve pause button
  
• Improve malformated JSON error handler
  
• Improve theme selection behavior
  
• Lock specialists until they are unlocked
  
• Improve new game button visibility
  
• Improve _announce game_ visibility
  
• Start the game unpaused (show a popup that pauses the game instead)
  
• Pause the game if the only developer is in vacations
  
• Close the load game popup if there is no savegame left