adding material editor menu

css/main.css

js/lattice/CompositeEditorLattice.js

js/main.js

js/materials/DMAMaterials.js

js/menus/CompositeMenuView.js

js/menus/MaterialEditorMenuView.js

js/menus/MaterialMenuView.js

js/menus/templates/MaterialEditorMenuView.html

js/menus/templates/MaterialMenuView.html

js/models/PList.js