Merge pull request #175 from mozilla/feature/ux-changes

src/assets/images/dropdown_arrow.png

src/assets/images/dropdown_arrow@2x.png

src/assets/images/level_background.png

src/assets/images/level_background@2x.png

src/assets/images/level_fill.png

src/assets/images/level_fill@2x.png

src/assets/images/mic_level.png

src/assets/images/mic_level@2x.png

src/assets/images/speaker_level.png

src/assets/images/speaker_level@2x.png

src/assets/stylesheets/audio.scss

src/assets/stylesheets/entry.scss

src/assets/stylesheets/exited.scss

src/assets/stylesheets/profile.scss

src/assets/stylesheets/shared.scss

src/assets/translations.data.json

src/hub.html

src/hub.js

src/react-components/entry-buttons.js

src/react-components/profile-entry-panel.js