Bug 821000: Add "Mobile; " to the B2G desktop user agent, r=gerv, r=cjones, a=blocking-basecamp

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extra : source : c34660d87368c8775cabe23c86347bf55ba4e57f
Bug 824199: Replace the marketplace-dev cert with the marketplace-prod test cert, r=rtilder, a=blocking-basecamp

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extra : source : 3e370d74c3a8a55b7b20590ba36de775e490f2d6
Bug 821207: Only allow signed apps to be installed from the Firefox Marketplace, and require all Firefox Marketplace apps to be signed, r=sicking, a=blocking-basecamp

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extra : source : ba13e1837b383c174966f7cfe38eb365f69b96ae