A quick update before the year ends, fixing some crashing bugs and all the rare-item quests.

• fix: you could swap weapon while in sniper-mode
• fix: made a few difficult building-jumps easier to do
• fix: inventory-crafting requirements now fit on smaller screen-formats
• fix: selecting some of the 2nd-tier skills could crash the game (using mouse or touchscreen)
• fix: limited the placement of rare-items
• fix: rare-item quests now function properly
• fix: entering/exiting rare-item quests would trigger unlimited looting