Adding Examples of Unit Model Costing Documentation

[MarcusHolly]

Fixes/Resolves:

Issue #1360

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.84%. Comparing base (4c0d270) to head (29a443a).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1373   +/-   ##
=======================================
  Coverage   93.84%   93.84%           
=======================================
  Files         339      339           
  Lines       35890    35890           
=======================================
  Hits        33682    33682           
  Misses       2208     2208           

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[agarciadiego]

General comment: superscripts and subscripts are not showing correctly un USD and in the parameter description. Also couldn't find CSTR, CSTR injection in the docs

[agarciadiego]

LGTM

[savannahsakhai]

LGTM, my only suggestion would be to delete the section in the CSTR page mentioned in my comment.

[savannahsakhai]

References

Aim to include at least one reference in most cases, but delete this section if no references used for cost relationships/default values

This section needs to be removed

[MarcusHolly]

Thanks for catching this - I just forgot to add it.