moved stan/gm/command.hpp to stan/ui/command.hpp; changed namespaces; moved tests
refactor: splitting write_iteration_csv() out of command.hpp
refactor: splitting write_csv() out of command.hpp
refactor: splitting write_stan() out of command.hpp; added unit tests
refactor: splitting write_model() out of command.hpp; added unit tests
refactor: splitting write_error_msg() out of command.hpp; added unit tests
refactor: splitting do_print() out of command.hpp
refactor: splitting print_progress() out of command.hpp
refactor: splitting run_markov_chain(); needs tests
refactor: splitting warmup() out of command.hpp; needs tests
refactor: splitting sample() out of command.hpp; needs tests
refactor: splitting init_* functions out of command.hpp; needs tests
moving namespace ui to common
adding a typedef to the stan model for use in CmdStan
moving src/test/CmdStan/command_test.cpp to cmdstan repository
refactor: moving src/test/CmdStan/fixed_param_test.cpp to cmdstan repository
refactor: moving src/test/CmdStan/optimization_output_test.cpp to cmdstan repository
refactor: moving src/test/CmdStan/print_test.cpp to cmdstan repository
refactor: moving src/test/CmdStan/gm/argument_configuration_test.cpp to cmdstan repository
refactor: removing CmdStan specific models