#786 Moved SymbolicNLP to core, removed casadi_nonlinear_programming library
#786 Removed NLPQPSolver public class
#786 Removed NLPImplicitSolver public class
#786 NewtonImplicitSolver public class
#786 SimpleHomotopyNLPSolver public class
#786 Removed SQPMethod public class
#786 Removed SCPgen public class
#786 Removed StabilizedSQPMethod public class
#786 Removed OOQP public class
#786 Build system cleanup
#1136 #786 Removed nonlinear_programming directory
#786 Fixed unit test