Add set pipefail in most framework scripts.

[mat]

Summary

set pipefail changes the pipeline return status from being the return
status of the last command to the last non 0 exit status of any command
in the pipeline. This is needed to make sure all the commands in a
pipeline did actually return a non 0 status and not only the last one.

[mat]

• fixup! Add set pipefail in most framework scripts.

[mat]

• Ignore grep return value.