Automated checkin: version bump for fennec 20.0b7 release. DONTBUILD CLOSED TREE a=release

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branch : MOBILE200b7_2013032600_RELBRANCH
Added FENNEC_20_0b7_RELEASE FENNEC_20_0b7_BUILD1 tag(s) for changeset 91fbf8798210. DONTBUILD CLOSED TREE a=release

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branch : MOBILE200b7_2013032600_RELBRANCH