Issues #705 and #706

[ASL-rmarshall]

Issue #705:

• Changed record_count.py to remerge results of a filtered grouped count onto the full list of (unfiltered) groups, filling any blanks with zero.
• Updated documentation in Operation.md as requested:
  • Changed single quotes to backticks for parameter names
  • Corrected "values(s)" typos
  • Added examples

Issue #706:

• Updated Operations.json schema to add group_aliases as an optional property (as a copy of group).
• Added grouping_aliases as a new operation parameter in operation_params.py.
• Mapped group_aliases to grouping_aliases in rule_processor.py.
• Added new methods to base_operation.py:
  • _rename_grouping_columns to rename each grouping column in grouping with the column name in the corresponding position in grouping_aliases.
  • _get_grouping_columns to create a list of grouping column names depending on whether grouping_aliases is specified or not.
• Updated documentation for both distinct and record_count in Operation.md to describe use of group_aliases.
• Created new _replace_nans_in_specified_cols_with_none static method in base_data_service.py.
• Updated _handle_grouped_results in base_operation.py to:
  • Include a call to _rename_grouping_columns if the grouping_aliases operation parameter is used (in addition to grouping).
  • Handle renamed grouping columns when merging the grouped results back onto the evaluation dataset.
  • Include a call to _replace_nans_in_specified_cols_with_none so that the NaN values created by the left join (when there is no grouped result for a particular group) do not cause an invalid JSON error when returned to the rules editor.
• Updated test_grouped_distinct in test_distinct.py to:
  • Add grouping_aliases parameter
  • Include an additional set of parameters that includes specification of grouping_aliases.
  • Update logic to test for correct application of grouping_aliases.
• Updated all tests in test_record_count.py:
  • test_filtered_record_count:
    • Moved filter specification to a parameter
    • Added a parameter set to confirm expected reporting of zero records matching filter.
  • test_grouped_record_count:
    • Added grouping_aliases parameter
    • Included a parameter set with a single-column grouping_aliases
    • Updated logic to test for correct application of grouping_aliases
  • test_multi_group_record_count:
    • Added grouping_aliases parameter
    • Included parameter sets with a grouping_aliases containing:
      • The same number of columns as grouping
      • Few columns than grouping
      • More columns than grouping
    • Updated logic to test for correct application of grouping_aliases
  • test_filtered_grouped_record_count:
    • Added grouping_aliases parameter
    • Included parameter set with:
      • A single-column grouping_aliases
      • Sets of values to test where:
        • There are no records matching the filter for an existing group (expecting zero to be reported as per #705 update)
        • The grouping_aliases column contains a grouping value not in grouping (expected None to be reported)
    • Updated logic to test for correct application of grouping_aliases

Additional changes:

• Corrected more typos in Operations.md:
  • Un-indented Operations in the example for distinct
  • Removed trailing backticks from lines in yaml block code in examples for label_referenced_variable_metadata and required_variables