Merge branch 'feature/composite-scheme' into feature/composite-scheme-other-fluxes

src/scheme/RoeViscousFormEulerianCompositeSolver_v2.cpp

src/scheme/RoeViscousFormEulerianCompositeSolver_v2_o2.cpp

src/scheme/RusanovEulerianCompositeSolver.cpp

src/scheme/RusanovEulerianCompositeSolver_o2.cpp

src/scheme/RusanovEulerianCompositeSolver_v2.cpp

src/scheme/RusanovEulerianCompositeSolver_v2_o2.cpp