Power Cycle module must export net loads

[tplobo]

Description of issue / requirement to address

Users should be able to export the net loads computed by the Power Cycle module if they want to import results into different codes or programs to plot/analyze/publish the results. The current implementation has not methods for this end.

Proposed solution

Implement a method in the power_cycle module to export net power loads to a JSON file. Exports should be one of two types:

• low-level detail: only system loads and net loads, separated by phases/pulses, so that simulation results can be used for analyses.
• high-level detail: cached version of full simulation results, that allow user to import them back into the power_cycle module without needing to re-run the simulation.

Alternative solutions

[je-cook]

As discussed elsewhere plain text files are not a good way of outputting data. It leads to situations like the EQDSK COCOS mess. Its much better to use a standard format like JSON because it is standardised (https://en.wikipedia.org/wiki/Json).

If a Reactor Designer want to output in a specific format thats up to them. In most cases we have a to_dict function to output the data that can be then used as the user desires without us directly supporting every format.

These days even excel is fine with JSON: https://superuser.com/questions/1772379/how-to-import-json-data-into-excel-columns

[CoronelBuendia]

Please no .txt files. We have a code-wide convention of dict->JSON as @je-cook says. It isn't perfect but is easy, low maintenance, and with good labelling, human readable.