Let people who run the nightly tester specify paths to external tests, instead

of having to hack the nightly tester script itself.

as an example, I use the following for my machine:

$HOME/llvm/utils/NightlyTest.pl -parallel -release -enable-llcbeta \
     -spec2000path /Volumes/ProjectsDisk/cvs/benchmarks/speccpu2000-llvm/benchspec/ \
     -povraypath /Volumes/ProjectsDisk/cvs/benchmarks/povray31 \
     -namdpath /Volumes/ProjectsDisk/cvs/benchmarks/namd

llvm-svn: 24136