i18n string dictionaries (#3532)

* TabBar & Settings -> Views i18n enabled

* Proxy i18n

* Settings i18n

* defaultLocale

* Introduce thin Translate wrapper

* PropTypes util caters for multiples

* Translate & LanguageSelector under ui

* Update location & proptypes

* Add UI Language selector

* German settings pages

* Add German language selection

* Corrected umlaut encoding

* Lint

* Re-apply pre-merge conflict changes

* better German i18n

* Language names in locale language

* i8n -> index

* Allow for development/production operation

* Use Yahoo react-intl (as opposed to react-i18nify)

* Use default messages wih expansions

* Remove non-reused variable definitions

* Use FormattedMessage directly, opens up WebPack & Babel opportunities

* Add flat to flatten

* Extract default messages via babel

* Webpack to aggegrate i18n defaultMessage

* Re-add react-intl after merge

* Update proptype references (merge)

* Strip down external dictionary

* i18n for dapps

* Restore tests submodule

* Allow language changes to reflect

* Style updates