Citizen inventory restocks only one itemstack at a time

[AngleWyrm]

EntityAIMaintainInventoryLevels performs one execution, but is spaced apart every five seconds. This should probably change so that if the citizen is within range of their assigned storage chest, they can get everything they need from it rapidly.

Probable solution is to modify shouldExecute() to separate out the two situations of "is close to assigned chest" or otherwise "has timer ticked down yet"

[AngleWyrm]

The "citizen got supplies" message seems to be happening too frequently, suggesting something is wrong with the way the citizens acquire desired inventory items.