Fix redundancies, repetitions, and cleanup rest

[bstellato]

The code repeats a lot, leading to potential issues. Here are some that should be fixed:

• Please removed unused comments. For example, there are several import ipdb; ipdb.set_trace() blocks
• In robust_problem.py you repeat several times solver_args={'solve_method': "ECOS"}. This dictionary should should be a constant LAYER_SOLVER in lropt.settings.
• Do not repeat dtype=torch.double. This should also be a constant DTYPE in lropt.settings