Move everything into teqp namespace

include/teqp/algorithms/VLE.hpp

include/teqp/algorithms/critical_tracing.hpp

include/teqp/algorithms/rootfinding.hpp

include/teqp/constants.hpp

include/teqp/containers.hpp

include/teqp/derivs.hpp

include/teqp/exceptions.hpp

include/teqp/filesystem.hpp

include/teqp/finite_derivs.hpp

include/teqp/json_builder.hpp

include/teqp/models/CPA.hpp

include/teqp/models/cubics.hpp

include/teqp/models/cubicsuperancillary.hpp

include/teqp/models/multifluid.hpp

include/teqp/models/multifluid_eosterms.hpp

include/teqp/models/pcsaft.hpp

include/teqp/models/vdW.hpp

include/teqp/types.hpp

interface/C/teqpc.cpp

interface/pybind11_wrapper.hpp