Bumping gaia.json for 2 gaia-central revision(s)

Truncated some number of revisions since the previous bump.

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https://hg.mozilla.org/integration/gaia-central/rev/af314d43e696
Author: Yuren Ju <yurenju@gmail.com>
Desc: Merge pull request #10427 from yurenju/bug848604

Bug 848604 - used apps.list to pick apps from apps/*, external-apps/* & ... r=timdream r=ochameau

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https://hg.mozilla.org/integration/gaia-central/rev/1fc023b64005
Author: Yuren Ju <yurenju@gmail.com>
Desc: Bug 848604 - used apps.list to pick apps from apps/*, external-apps/* & GAIA_DISTRIBUTION_DIR

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "469f2a2026b4e67c19e0fedc4215fa61418870a9", 
+    "revision": "af314d43e69644faa8ca6ab0c0dedfda63035fdf", 
     "repo_path": "/integration/gaia-central"
 }