Improvements in Trigger ART exec scripts
The following changes are made:
- Some steps of our post-processing scripts printed too verbose information to stdout while also saving it to individual log files. Now their output is only redirected to log. These steps are: RootComp, histSizes and checklog for warnings.
- Generate an empty PoolFileCatalog.xml file before running athena, as advised by @tcuhadar. This should prevent incorrect error handling on the grid in case of athena crashes / memory cut-off. It is harmless for successful jobs and for build tests.
- Protect chainDumpWorkaround.py from dereferencing a nullptr if histogram doesn't exist.