Automated checkin: version bump for firefox 23.0 release. DONTBUILD CLOSED TREE a=release

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branch : GECKO230_2013080122_RELBRANCH
Added FIREFOX_23_0_RELEASE FIREFOX_23_0_BUILD2 tag(s) for changeset 5efffaf39814. DONTBUILD CLOSED TREE a=release

--HG--
branch : GECKO230_2013080122_RELBRANCH