v1.1 Quandary for pure-state preparation and gate optimization

• Generalizes the ground-state optimization to include a general pure target state. Optimization target can now either be a logical gate transformation, or a pure state for state preparation.
• Implements pure-state preparation as published in https://arxiv.org/abs/2106.09148
• Some configuration options changed! New options now include 'optim_target', 'optimal_objective'. Compare the 'config_template.cfg'.
• Adding new options for initial states, including 3state initialization for gate optimization.
• Generalization of the integral penalty term
• Improved user guide