fix conflict

public/index.html

src/components/ContentTabItem/ContentTabChild.js

src/components/ContentTabItem/index.js

src/components/CourseCard/index.js

src/components/Footer/Wrapper.js

src/components/Footer/index.js

src/components/Header/HeaderLink.js

src/components/Header/Img.js

src/components/Header/NavBar.js

src/components/Header/index.js

src/components/Header/messages.js

src/components/Header/tests/A.test.js

src/components/Header/tests/Img.test.js

src/components/Header/tests/__snapshots__/A.test.js.snap

src/components/Header/tests/__snapshots__/Img.test.js.snap

src/components/Header/tests/__snapshots__/index.test.js.snap

src/components/Header/tests/index.test.js

src/components/Video/Wrapper.js

src/components/Video/index.js

src/containers/AddVideoPage/index.js