Adjusted the upper limits of all dispatchable and must-run plants to be based on their capacity rather then their production. This fixes the behavior that plants with very few FLHs (e.g., Wartsilla plant) have ridiculously high slider maxima. Fixes https://github.com/quintel/etsource/issues/863
Cleaned up input statements and gquries by using the new maximum_yearly_electricity_production_per_unit converter method.
Merge pull request #889 from quintel/intuitive_slider_caps

intuitive slider caps