dynamic biosphere builder adds dynamic_biomatrix entries multiple times if time-mapped producer is multiple times in the timeline

[muelleram]

it would the same entries twice with DynamicBiosphereBuilder.add_matrix_entry_for_biosphere_flows() twice and dynamic_biomatrix = sp.coo_matrix((self.values, (self.rows, self.cols)), shape) would add up the amounts for these row-col pairs:

This is not a problem as soon as the time-mapped producer is occurring at a different time, because it gets it's own column then.

[muelleram]

#67 not quite the same but related issue.