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

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https://hg.mozilla.org/integration/gaia-central/rev/a945fd2a40ba
Author: Yuren Ju <yurenju@gmail.com>
Desc: Merge pull request #10880 from yurenju/bug848604-2nd

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

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https://hg.mozilla.org/integration/gaia-central/rev/ab587914414c
Author: Yuren Ju <yurenju@gmail.com>
Desc: Bug 848604 - used apps.list to pick apps from apps/*, external-apps/* & GAIA_DISTRIBUTION_DIR