Stash gives trade xp and changes prices

[Ahad88]

Stash is broken. I left my food in the city stash for when I go on large campaigns. It gave me trade skills, crashed food prices in the city, led to starvation and by the time my recruitment was finished a portion of my main army in the garrison died of starvation when I had 2000 grain and fish in the stash and market had no food since its too cheap.