Berserkergang changed to Looting

I feel there is an opportunity missed with Vikings.

Looting.

Change Berserkergang to "damage dealt by Berserkers to enemy buildings grants gold".

• narrows the bonus to Berserkers to incentivise their use over other infantry options.
• Incentivise castle/early imp aggression, which is where their strength lies.
• In-line with their "historical" role as raiders and pillagers.
• Berserkers cool AF.