mol-plugin-ui: added Button common ctrl

src/mol-plugin-ui/base.tsx

src/mol-plugin-ui/camera.tsx

src/mol-plugin-ui/controls/action-menu.tsx

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

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

src/mol-plugin-ui/custom/volume.tsx

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

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

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

src/mol-plugin-ui/structure/components.tsx

src/mol-plugin-ui/structure/focus.tsx

src/mol-plugin-ui/structure/generic.tsx

src/mol-plugin-ui/structure/measurements.tsx

src/mol-plugin-ui/structure/selection.tsx

src/mol-plugin-ui/structure/source.tsx

src/mol-plugin-ui/viewport/help.tsx

src/mol-plugin-ui/viewport/screenshot.tsx