Automated checkin: version bump for thunderbird 24.0b2 release. DONTBUILD CLOSED TREE a=release

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branch : GECKO240b2_2013082815_RELBRANCH
Added THUNDERBIRD_24_0b2_RELEASE THUNDERBIRD_24_0b2_BUILD1 tag(s) for changeset 0c687b12a2fe. DONTBUILD CLOSED TREE a=release

--HG--
branch : GECKO240b2_2013082815_RELBRANCH