Bumping gaia.json for 2 gaia-1_3 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_3/rev/d571d8bc76b1
Author: Fabien Cazenave <fabien@cazenave.cc>
Desc: Merge pull request #14884 from flodolo/bug950171

Bug 950171 - [settings] "Improve Firefox OS" title displayed as "Improve {{brandShortName}}"
(cherry picked from commit b3baaadf40db67d8e5812de7a7bb0cdea26844b1)

(cherry picked from commit 1a5b5d779c5482124b4887cc40c7b853fcd4759a)

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https://hg.mozilla.org/integration/gaia-1_3/rev/a667c67e9383
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Merge pull request #14224 from flodolo/separate_header

Bug 944749 - [Settings][l12y] Use different labels for menu items and headers, r=kaze
(cherry picked from commit 588a3e02c4ace3b3341ba1f6bb7274120b53b2b3)

Removed change to apps/settings/elements/improve_browser_os.html which is going to be fixed by Bug 950171 (originally follow-up of this bug)

Conflicts:
	apps/settings/elements/downloads.html
	apps/settings/locales/settings.en-US.properties

(cherry picked from commit d256a30ef3fbdf8d70cfff2c12926df2ab9bf903)