xcpretty should exit with an error code if it sees BUILD FAILED

[zachriggle]

Currently, xcpretty always returns zero. It should look for "BUILD SUCCEEDED" and "BUILD FAILED" in the xcodebuild output and exit accordingly.

This makes it hard to do e.g.

if xcodebuild build foo | xcpretty; then
  do_things_with_build_results
else
  do_things_with_build_error
fi

[thermopyle]

Try set -o pipefail && xcodebuild build foo | xcpretty to get the pipe to return an error if any of the piped commands return an error.

[zachriggle]

Thanks!