Changes proposed in this pull request:

• Function server.run_sensitivity_analysis_step to perform one step of a sensitivity analysis
• Function utils.nested_dict_crawler to return mapping of path within a nested dict to the keys at the lowest nested level
• Enable capacity optimization for storage assets in the epa
• Input timeseries is now not returned to epa in utils.data_parser.py
• Add test class test_utils.TestAccessKPIs to test the nested dict utils functions
• Make the utils function get_nested_valueand set_nested_value raise a Key error with a traceback indicating where in the nested dict this key was missing to help debugging

#923 has to be merged prior to merge this PR

The following steps were realized, as well (if applies):

• Use in-line comments to explain your code
• Write docstrings to your code (example docstring)
• For new functionalities: Explain in readthedocs
• Write test(s) for your new patch of code (pytests, assertion debug messages)
• Update the CHANGELOG.md
• Apply black (black . --exclude docs/)
• Check if benchmark tests pass locally (EXECUTE_TESTS_ON=master pytest)

_{For more information on how to contribute check the CONTRIBUTING.md.}