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.

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

Generate `locale/messages.json` from available languages in `translations`.  If there are no translations for a given language (from `languages.json`) it just skips it, react-intl will use the default english strings.

Just using English, French and Spanish for testing right now.