Factor out S3 config functionality to a class with static methods.

To make it easier to call from other code.  Also, add a couple
utility methods to call from RemoteApi.
add and enable ca
add and enable uk_UA
add and enable nl
add and enable fr_CA
add and enable cs
add and enable sv
add and enable hr
add and enable ru_RU
add and enable sk
add and enable de
add and enable fr_FR
add and enable nb
add and enable ug
add and enable ja
add and enable it
add and enable he_IL
add and enable ko
regenerate emails
add missing anchors for lang links in how-to-get-lantern email template