Bumping gaia.json for 3 gaia revision(s) a=gaia-bump

========

https://hg.mozilla.org/integration/gaia-central/rev/742818009039
Author: Diego Marcos <diego.marcos@gmail.com>
Desc: Merge pull request #16315 from dmarcos/bug960611+bug958200

Bug960611+bug958200

========

https://hg.mozilla.org/integration/gaia-central/rev/593f19a43268
Author: Diego Marcos <diego.marcos@gmail.com>
Desc: Bug 958200 - [Camera] Update Camera app to use new CameraControl API

========

https://hg.mozilla.org/integration/gaia-central/rev/6a16d0c35340
Author: Wilson Page <wilsonpage@me.com>
Desc: Bug 960611 - [Camera] Create mechanism to save/load user settings
Bumping manifests a=b2g-bump