Bug 932176: Add preference to control whether OCSP GET is used, off by default, r=cviecco

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extra : rebase_source : 7cbc273155d04bc64a110eda9216c6f727ce0c18
Bug 861266: Enable TLS 1.2 by default, r=briansmith

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extra : rebase_source : 4f28724d58791e1ee0e281ff48232f5aaca2048f