Automated checkin: version bump for firefox 25.0b6 release. DONTBUILD CLOSED TREE a=release

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branch : GECKO250b6_2013100723_RELBRANCH
Added FIREFOX_25_0b6_RELEASE FIREFOX_25_0b6_BUILD1 tag(s) for changeset 373f0e83dc36. DONTBUILD CLOSED TREE a=release

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branch : GECKO250b6_2013100723_RELBRANCH