Price Elasticity Define supply must contain fleet indexes

[joeb]

In the Price elasticity Define supply dialogue the user can select just a group to define the landings. This implies that all fleets that land this group are included with the same weight. This defines the fleet as having a zero index. Fleets can not have a zero index in the code and this means that this value is not used.

One solution would be to added a Group/Fleet? combo for each fleet that lands this group.

Another would be to not allow adding of just groups the user would always need to select a group/fleet combo

This is probable the cause of the Ecopath weight bug

[jeroens]

The user interface right now will only accept landings for both group and fleet.