Add a basic algorithm comparison routine

CMakeLists.txt

apps/CMakeLists.txt

apps/compare_convergence.cpp

optimization/optimizers/cma_es/CMakeLists.txt

optimization/optimizers/cma_es/cma_es.h

optimization/optimizers/cma_es/cma_es_log.h

optimization/optimizers/cma_es/main.cpp

...tion/optimizers/conjugate_gradient_descent/CMakeLists.txt

...s/conjugate_gradient_descent/conjugate_gradient_descent.h

optimization/optimizers/conjugate_gradient_descent/main.cpp

optimization/optimizers/gradient_descent/CMakeLists.txt

optimization/optimizers/gradient_descent/gradient_descent.h

...zation/optimizers/gradient_descent/gradient_descent_log.h

optimization/optimizers/gradient_descent/main.cpp

optimization/optimizers/nelder_mead/CMakeLists.txt

optimization/optimizers/nelder_mead/main.cpp

optimization/optimizers/nelder_mead/nelder_mead.h