Implement Temperature-dependent Solid Volumetric Heat Capacity

[sytuannguyen]

This PR is part of the Non-Linear Thermal Behavior project. It aims to implement the linear temperature dependent of the solid volumetric specific heat capacity.

C = C0 + dC_dT * (T-T0)

where C0 is the reference solid volumetric heat capacity at the reference temperature T0 and dC_dT is the gradient of the volumetric heat capacity w.r.t. temperature. They are both provided by users in XML input files.

The existing linear constitutive model corresponds to the particular case with dC_dT = 0.

• [x] Implement the constitutive model
• [x] Validation script and examples
• [ ] Unit tests
• [ ] Integrated test
• [ ] Change the xml files