Proposed changes

Add a minimum temperature option for the Ideal Fluid equation of state.
The lower bound of specific internal energy is currently determined from the lower bound of temperature, which defaults to 0 for the ideal fluid equation of state. This new option provides a simple way of enforcing a nonzero lower bound on the specific internal energy.
For those who prefer the default lower bound on temperature, MinTemperature can be set to 0.0 in the input file. Additionally, using the single-argument constructor will set the minimum temperature to its default value of 0.

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• The code is documented and the documentation renders correctly. Run
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• The code follows the stylistic and code quality guidelines listed in the
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• The PR lists upgrade instructions and is labeled bugfix or
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