improved lighting

src/apps/basic-wrapper/index.ts

src/examples/proteopedia-wrapper/index.ts

src/mol-canvas3d/camera/util.ts

src/mol-canvas3d/canvas3d.ts

src/mol-geo/geometry/color-data.ts

src/mol-gl/renderable/direct-volume.ts

src/mol-gl/renderable/schema.ts

src/mol-gl/renderer.ts

src/mol-gl/shader/chunks/apply-light-color.glsl

src/mol-gl/shader/chunks/assign-normal.glsl

src/mol-gl/shader/chunks/common.glsl

src/mol-gl/shader/chunks/light-frag-params.glsl

src/mol-gl/shader/chunks/normal-frag-params.glsl

src/mol-gl/shader/direct-volume.frag

src/mol-gl/shader/mesh.frag

src/mol-gl/shader/spheres.frag

src/mol-gl/shader/utils/attenuation.glsl

src/mol-gl/shader/utils/oren-nayar-diffuse.glsl

src/mol-gl/shader/utils/phong-specular.glsl

src/mol-plugin/context.ts