Merge pull request #4974 from ericrosenbaum/feature/sound-editor-selection4

src/components/sound-editor/sound-editor.css

src/components/sound-editor/sound-editor.jsx

src/components/waveform/waveform.jsx

src/containers/audio-selector.jsx

src/containers/audio-trimmer.jsx

src/containers/record-modal.jsx

src/containers/sound-editor.jsx

src/lib/audio/audio-effects.js

src/lib/audio/audio-util.js

src/lib/audio/effects/echo-effect.js

src/lib/audio/effects/fade-effect.js

src/lib/audio/effects/mute-effect.js

src/lib/audio/effects/robot-effect.js

src/lib/audio/effects/volume-effect.js

test/__mocks__/audio-effects.js

test/integration/sounds.test.js

.../unit/components/__snapshots__/sound-editor.test.jsx.snap

test/unit/components/sound-editor.test.jsx

test/unit/containers/sound-editor.test.jsx

test/unit/util/audio-effects.test.js