* removed anything that was made redundant by scratch-l10n.
* updated a string that wasn’t following conventions
* added .tx/config so developers can start updating Transifex when there are new strings

Changed color and background-color as requested; temporarily hidden the icon

the background was white and the font color was too - I changed it to be black instead

move all locale data (react-intl/locale-data and gui messages) into locale.js. This also makes switching to an external node package easier because the package just needs to export the same thing as locale.js.

Dynamic import didn’t do what we wanted, so just added `npm run i18n:msgs` to the start command. This is just temporary. Other changes as requested:
* exports in one place
* loc=> locale

Also fixed use of require for localeData to use dynamic import (this one works), so the babelrc changes are needed, otherwise import as a function is not recognized.

Added language-selector component and container. Replaced lib/intl.jsx with reducers/intl.js and added updateIntl to handle language changes.

Moved languages.json into src