Define Resource Transfer for Producer using External Function source

[GabrielSoto-INL]

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Pull Request Description

What issue does this change request address?

#253

What are the significant changes in functionality due to this change request?

Added ability to call an external function within the Pyomo Dispatcher (namely, in _create_transfer). The method now checks for transfer type: either a linear or function source.

If it is a function source, the user can specify 2 types of outputs from the function call. They can:

1. provide a list of ratios indexed by the pivotParameter (e.g., a linear relationship per time step) or
2. provide a Pyomo constraint.

For option (1), this is a nested dictionary where the key entry is the resource name and the associated item is the array of ratios. Note that Pyomo Dispatch will check that the ratio array length matches pivotParameter length. For option (2), it is also a nested dictionary, but the keys are the names of the constraint and the item is the Pyomo Constraint. The dispatcher will loop through the nested dictionaries and set the constraints to the Pyomo model. Regression tests have been added for each of these options in integration_tests/mechanics. Documentation has also been updated.

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For Change Control Board: Change Request Review

The following review must be completed by an authorized member of the Change Control Board.

• 1. Review all computer code.
• 2. If any changes occur to the input syntax, there must be an accompanying change to the user manual and xsd schema. If the input syntax change deprecates existing input files, a conversion script needs to be added (see Conversion Scripts).
• 3. Make sure the Python code and commenting standards are respected (camelBack, etc.) - See on the wiki for details.
• 4. Automated Tests should pass.
• 5. If significant functionality is added, there must be tests added to check this. Tests should cover all possible options. Multiple short tests are preferred over one large tes.
• 6. If the change modifies or adds a requirement or a requirement based test case, the Change Control Board's Chair or designee also needs to approve the change. The requirements and the requirements test shall be in sync.
• 7. The merge request must reference an issue. If the issue is closed, the issue close checklist shall be done.
• 8. If an analytic test is changed/added, the the analytic documentation must be updated/added.
• 9. If any test used as a basis for documentation examples have been changed, the associated documentation must be reviewed and assured the text matches the example.