Aurora: string changed for New Tab introduction

[Francesco Lodolo [:flod]]

Hi,
a string change just landed on mozilla-aurora for the New Tab intro:
http://hg.mozilla.org/releases/mozilla-aurora/rev/2ce1d8162c4a

The current message was considered poorly worded: it seemed that you
need to select "Show blank page" to stop sending data to Mozilla, while
it's enough to deselect "Include suggested sites".

This new string *landed without a new ID* on purpose: we're in the
middle of the cycle, several locales already translated the string.
While the old string might be inaccurate, displaying it instead of an
English string seems a better compromise.

You should obviously update your localization if you can, but the
dashboard won't report the missing string. It will happen on next cycle
on Aurora, since in Firefox 41 the string landed with a new ID.

Side notes on the New Tab tour:
* If you want to test the tour, set browser.newtabpage.updateIntroShown
to false in about:config and open a new tab.
* There are still some layouts issues with the menu and long text. [1]
* The hard-coded "Example Title" has been replaced with "mozilla.org"
(not yet on Aurora). [2]

Francesco

[1] https://bugzilla.mozilla.org/show_bug.cgi?id=1164594
[2] https://bugzilla.mozilla.org/show_bug.cgi?id=1165430