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

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branch : MOBILE200_2013032617_RELBRANCH
Added FENNEC_20_0_RELEASE FENNEC_20_0_BUILD1 tag(s) for changeset 6405cfc13ccd. DONTBUILD CLOSED TREE a=release

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branch : MOBILE200_2013032617_RELBRANCH