Merge pull request #646 from smuzaffar/IB/CMSSW_5_3_X/osx107_amd64_gcc462

updated scram version to V2_2_5_pre7 to avoid perl module dependency
Merge pull request #656 from smuzaffar/IB/CMSSW_5_3_X/osx107_amd64_gcc462

updated scram version to V2_2_5_pre8 which now prints only warning for scram_arch/os mismatch
updated config tag to V05-01-24-00 for 53X
updated for 5.3.18
updated config tag to V05-01-27-00