Bug 910014 - Success message on Firefox & You signup

When you signup for the Firefox & You newsletter at
https://www.mozilla.org/firefox/os/ or
https://www.mozilla.org/firefox/fx, change the success
message.
Template: improve l10n for strings on privacy contact form
CSS: added clear:both to header, removed top margin, added padding on top only under 760px (when the navigation menu is collapsed)
Merge pull request #1200 from dpoirier/bug-910014-ff-and-you-signup-message

Bug 910014 - Success message on Firefox & You signup
Merge pull request #1219 from pascalchevrel/Bug-881754_firefoxnew_locales_redirects

Bug 881754: activate /new page for an, ast, br, fi, pt-PT
Bug 892470: activate plugincheck for bg, id, pa-IN
Merge pull request #1205 from flodolo/l10n_privacy

Bug 887535 - Improve CSS and strings for l10n on privacy contact form
Fix issue with undefined translations variable.

If the view doesn't use RequestContext the `translations`
variable won't exist, and the `dictsort` filter will raise
and exception.
Merge pull request #1220 from pmclanahan/fix-404-page

Fix issue with undefined translations variable.
Bug 915845: Fix unsupported details page.
Merge pull request #1221 from pmclanahan/re-enable-unsupported-page

Bug 915845: Fix unsupported details page.
adding deploy scripts from current chief bedrock environments.
Merge pull request #1222 from cturra/master

adding deploy scripts from current chief bedrock environments.
Bug 900156: add Hungarian (hu) to supported locales for the newsletter
Merge pull request #1223 from pascalchevrel/Bug-900156-newsletter_l10n

Bug 900156: add Hungarian (hu) to supported locales for the newsletter
Bug 881754: add ar & ca locales to firefox/new redirects