Add daily energy balance to fitting script

Created by: Lars Dalby

Imported comments:

By Lars Dalby on 2018-06-26T08:00:47.808Z

closed via merge request !23

By Lars Dalby on 2018-06-26T08:00:47.538Z

mentioned in commit 14e1f87e

By Lars Dalby on 2018-06-26T08:00:11.978Z

mentioned in merge request !23