Unify stochasticity naming for dispersers #204
Description
Stochasticity for creation of dispersers is called "dispersers stochasticity" in simulation, host pool and actions, but it is called "generate stochasticity" in model to distinguish it from "dispersal stochasticity" for kernel.
This creates confusion when switching between the model level and the action-host-pest level.
New naming is needed which is applicable to all parts of the code or which does not use similar names for different things.