[0.10.x][kovarex] Un-researching toobelt crashes the game

[Rseding91]

This is a bit of a edge case bug but a bug non the less.

If you un-research the toolbelt the game will crash.

Steps to reproduce:

• Load a new or existing game
• Complete the toolbelt research (either normally or via console command)
• insert some items into the toolbelt (unsure if this step is required)
• Un-research the toolbelt with the console command: game.forces.player.technologies["toolbelt"].researched = false

At this point the game will crash to desktop.

[kovarex]

Thank you for the report, the issue is fixed for 0.10.9