Time series does not unload when "None" data set is selected

[joeb]

More time series wows.

• Open a model with time series data, Georgia Strait.
• Run Ecosim and look at the graph output.
• Load a time series.
• Run Ecosim and the output should be different.
• Go back to the Time series interface and select the 'none' dataset option, this should unload the time series from the interface.
• Run Ecosim the ouput will not have changed from the run with time series, the observed data points will be gone but the output will be the same.

[jeroens]

Fixed pragmatically; unloading TS will simply reload the Ecosim scenario.
This should also be applied when changing the # of applied TS: TS should be re-applied in a freshly reloaded Ecosim scenario