Automated checkin: version bump for fennec 20.0b2 release. DONTBUILD CLOSED TREE a=release

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branch : MOBILE200b2_2013022811_RELBRANCH
Added FENNEC_20_0b2_RELEASE FENNEC_20_0b2_BUILD2 tag(s) for changeset 89d8e008eda9. DONTBUILD CLOSED TREE a=release

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branch : MOBILE200b2_2013022811_RELBRANCH