Fix test runner to catch segfaults
Fix test runner to catch segfaults

They were silently passing due to a change in the semantics
of the Sh.py nee PBS library we use.

Former-commit-id: f1d26cef9bfbca24788747af6dc1e718a6dd65c2
Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide