Allow for more generic inputs (e.g., quantities with units)

[dahong67]

Could be nice to allow for more general input types (if we don't already). For example, data often come with units. It would be fun if HePPCAT could handle this directly and produce, e.g., noise variance estimates with units attached.

[JeffFessler]

e.g., ala https://github.com/PainterQubits/Unitful.jl
neat idea!