Option to constrain initial CAPEX

[adfarth]

Adds inputs: min_initial_capital_costs_before_incentives and max_initial_capital_costs_before_incentives which constrain a calculation equivalent to the result Financial.initial_capital_costs.

Note: The Financial results initial_capital_costs and initial_capital_costs_after_incentives do not currently account for the third_party_factor. I.e., they indicate the cost to the third party but not the capex from the host's perspective. See this result which shows the initial capex and lifecycle capex as different despite no replacements or incentives: https://reopt.nrel.gov/tool/results/c6164b3a-e59b-4efe-b034-0397a0429960. This is the current behavior and is persisted in this PR.

[zolanaj]

Looks good, thanks a bunch @adfarth! I checked and ran a separate local test to confirm the function of the constraints, and I like the moving of the financial expression into a new function before the objective. I have one quick question on outside test changes and a couples opinions on TODO's in the function, but this is ready to merge as-is, once the changelog is updated!

[zolanaj]

@adfarth in addition to the changelog update, I added an error check for min > max capital cost input. Let me know if you have any concerns - thanks!