Automated checkin: version bump for thunderbird 26.0b1 release. DONTBUILD CLOSED TREE a=release

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branch : GECKO260b1_2013111313_RELBRANCH
Added THUNDERBIRD_26_0b1_RELEASE THUNDERBIRD_26_0b1_BUILD1 tag(s) for changeset d813a0e948b9. DONTBUILD CLOSED TREE a=release

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branch : GECKO260b1_2013111313_RELBRANCH