Merge branch 'master' into volume

src/mol-plugin/behavior/behavior.ts

src/mol-plugin/behavior/static/state.ts

src/mol-plugin/command.ts

src/mol-plugin/skin/base/components/transformer.scss

src/mol-plugin/state/actions/structure.ts

src/mol-plugin/state/transforms/model.ts

src/mol-plugin/ui/plugin.tsx

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

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

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

src/mol-plugin/ui/state/update-transform.tsx