Merge pull request #4 from luna215/canvas

src/mol-geo/geometry/direct-volume/direct-volume.ts

src/mol-geo/geometry/direct-volume/transfer-function.ts

src/mol-plugin/skin/base/components/line-graph.scss

src/mol-plugin/skin/base/ui.scss

...ol-plugin/ui/controls/line-graph/line-graph-component.tsx

src/mol-plugin/ui/controls/line-graph/point-component.tsx

src/mol-plugin/ui/controls/parameters.tsx

src/mol-plugin/ui/state.tsx