Refactored builder class to use new mphys import procedures and variable naming convention
Changing how coupled tacs problems are setup in builder. No longer using a coupled boolean flag, instead user passes forces to be added to RHS as list of str
MPhys examples and tests in tacs repo are updated and working (using this PR of MPhys)
coupledboolean flag, instead user passes forces to be added to RHS as list of str