mol-state & mol-plugin: updating

src/apps/viewer/index.html

src/mol-app/component/parameters.tsx

src/mol-plugin/context.ts

src/mol-plugin/ui/controls.tsx

src/mol-plugin/ui/plugin.tsx

src/mol-plugin/ui/state-tree.tsx

src/mol-state/immutable-tree.ts

src/mol-state/selection.ts

src/mol-state/state.ts

src/mol-state/transformer.ts