I18n of devise views + mailers

[mooreniemi]

devise_i18n give us a lot of locales for free. I tested this using a headers setting extension for Chrome and editing Accept-Language. But some pages, like the sign up page, are still pretty sparse.

The branch is up on staging now.

I also incidentally updated capybara (no help to spec stability sadly) and many of the forms switched from form_for to simple_form_for and I am not certain the error handling is great.

screenshots of zh

(note I fixed "remember me" see comments further down)

[mooreniemi]

Fixed this now:

[mooreniemi]

So far so good on staging and Prod. I will keep an eye out for errors.