Add the ability to use a reference material (e_ref=....) directly with the display_results() method

[Agent6-6-6]

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Feature Request

As per the issue title, as I understand it from reviewing the code for display_results() method:-

• You can currently only use the reference material directly with the individual methods for retrieving singular results for a composite analysis (i..e the get_.... methods).

Think it would be helpful to be able to use e_ref directly with display_results() method and have it return all of the relevant parameters output in terms of the reference material. Include e_ref in the display_results() output when used in this manner for clarity.

Believe this would also possibly help with some of the interpretation issues seen in the past with the composite results (given they are E weighted outputs vs transformed properties) if there is an option to output all of the results in terms of a provided reference material.