Updated copyright notice for 2019 (frustmag)

config_policy.hpp

config_sim_base.hpp

frustmag/concepts.hpp

frustmag/config_frustmag_sim.hpp

frustmag/frustmag.hpp

frustmag/frustmag_config_policy.hpp

frustmag/hamiltonian/heisenberg.hpp

frustmag/hamiltonian/ising.hpp

frustmag/lattice/bravais.hpp

frustmag/lattice/chain.hpp

frustmag/lattice/dice.hpp

frustmag/lattice/honeycomb.hpp

frustmag/lattice/kagome.hpp

frustmag/lattice/ortho.hpp

frustmag/lattice/triangular.hpp

frustmag/main.cpp

frustmag/observables.hpp

frustmag/site/spin_O3.hpp

frustmag/site/spin_Z2.hpp

frustmag/std_concepts.hpp