add functionality to get temperature from enthalpy

[anderson2981]

Questions for the review:

• [x] Is the scope and purpose of the PR clear?
  • [ ] The PR should have a description.
  • [ ] The PR should have a guide if needed (e.g., an ordering).
• [x] Is every top-level method and class documented? Are things that should be documented actually so?
• [x] Is the interface understandable? (I.e. can someone figure out what stuff does?) Is it well-defined?
• [x] Does the implementation do what the docstring claims?
• [x] Is everything that is implemented covered by tests?
• [x] Do you see any immediate risks or performance disadvantages with the design? Example: what do interface normals attach to?

[anderson2981]

probably could add some tests to check that enthalpy matches with temperature and energy.

Should also be able to refactor into 1 function that does both, like in pyrometheus.

[MTCam]

probably could add some tests to check that enthalpy matches with temperature and energy.

Should also be able to refactor into 1 function that does both, like in pyrometheus.

Cool, just added #1037 to align this with mixture fraction eos changes. Unified energy/enthalpy interface and update func.