bug 986990: Modify test channel names to support releases on Balrog - support new test channel substitutions; use local test channel for update verify. r=nthomas

--HG--
branch : production-0.8
extra : transplant_source : %FDw%15s%E0%D8%01%1C%A9%ECb%1E%C1v%80%DC%B2%B3%EF%3D