Do not search for compilers in sft.cern.ch and AFS
AFS is never searched, =/cvmfs/sft.cern.ch= ise serached only if the environment variable USE_SFT
is set.
Also fixed lookup for clang 6.0.0
Edited by Marco Clemencic
AFS is never searched, =/cvmfs/sft.cern.ch= ise serached only if the environment variable USE_SFT
is set.
Also fixed lookup for clang 6.0.0