Hotfix 0.5.7.13

Hotfix:

• Save game bugs solved and stability of the game increased
  

Adjustment:

• Logic of “Pact of Prosperity” (Relic, common), “Quarry Legacy” (Relic, rare) adapted so that their conditions apply across wave phases for Economy and Defense phase. -> No more distribution of 3 gold / 30 stone “for free”
  

Further Improvements:

• Added 2 new options under the “General” settings item:
  - Run in background
  - Play music in background
  
• Minor UI optimizations (Purchases in the market / calculation of tower price inflation)
  

Restored changes from 0.5.7.12:
https://store.steampowered.com/news/app/3086510/view/4514387160627548368