Figure label naming

[jaredthomas68]

Figure label naming

This PR changes figure text to use sentence case and also switches all internal and plotting uses of "metric tonne" and "tonne" to "metric ton".

PR Checklist

• CHANGELOG.md has been updated to describe the changes made in this PR
• Documentation
  • Docstrings are up-to-date
  • [-] Related docs/ files are up-to-date, or added when necessary
  • [-] Documentation has been rebuilt successfully
  • Examples have been updated
• Tests pass (If not, and this is expected, please elaborate in the tests section)
• PR description thoroughly describes the new feature, bug fix, etc.

Related issues

Impacted areas of the software

• examples/reference_plants/01-onshore-steel-mn/onshore-steel-mn.py
• greenheart/simulation/technologies/hydrogen/desal/desal_model_eco.py
• greenheart/simulation/technologies/hydrogen/electrolysis/pem_mass_and_footprint.py
• greenheart/simulation/technologies/hydrogen/h2_storage/pressure_vessel/compressed_gas_storage_model_20221021/Compressed_all.py
• greenheart/simulation/technologies/hydrogen/h2_storage/pressure_vessel/compressed_gas_storage_model_20221021/Compressed_gas_function.py
• greenheart/simulation/technologies/offshore/fixed_platform.py
• greenheart/simulation/technologies/offshore/floating_platform.py
• greenheart/simulation/technologies/steel/steel.py
• greenheart/tools/eco/electrolysis.py
• greenheart/tools/eco/finance.py
• greenheart/tools/eco/hydrogen_mgmt.py
• greenheart/tools/eco/utilities.py
• tests/greenheart/test_hydrogen/test_pressure_vessel.py

Additional supporting information

The catalyst for this change was feedback from the NREL communications team during review of the green steel reference system design document.

Test results, if applicable

[johnjasa]

Non-blocking question: I see there are still places that are relatively external facing (.ipynb examples) where we say "tonnes". Did you leave those in on purpose or should those be changed as part of this PR? To be clear, I don't care to update any references in the to_organize folder.

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[jaredthomas68]

Non-blocking question: I see there are still places that are relatively external facing (.ipynb examples) where we say "tonnes". Did you leave those in on purpose or should those be changed as part of this PR? To be clear, I don't care to update any references in the to_organize folder.

I intended to only leave "tonnes" in places where it would be breaking (e.g. calling dependencies that use "tonnes"). I had ignored the to_organize directory, but the others I had missed by not search .ipynb or .md extensions. Thanks for the catch. I went ahead and updated everything non-breaking (e.g. input files for ORBIT)