Fix bogus logic in capabilities file creation

rootcling was checking for the wrong string to be non empty.
80 Cols.
Add getter and silence a warning.
Disable tests on SLC6 32 bit.
fix compile error flagged by latest clang++ 3.4.
fix warnings flagged by latest clang++ 3.4.
xlc compiler on OSX is not anymore supported.
simplify detection of OSXSDK and IOSSDK.
fix warning coming from latest clang++ from Xcode 5.
set MACOSXVERSION also when cocoa is disabled.
Only register temporaries for which lifetime extension is actually required.
Implement TMath::Abs in term of std::abs
See ROOT-5473
Implement TMath::Abs in term of std::abs
See ROOT-5473
xlc compiler on OSX is not anymore supported.
simplify detection of OSXSDK and IOSSDK.
set MACOSXVERSION also when cocoa is disabled.
Only register temporaries for which lifetime extension is actually required.
Merge branch 'master' of https://root.cern.ch/git/root
Try to fix a compilation error on some platform.
use ::abs for integer types instead of std::abs
Fix bug when no rootmapfilename is in input to genreflex