Merge branch 'devel' into feature/staging

WARNING: This was a non-trivial merge, please pay attention!!

Conflicts:
    src/radical/pilot/agent/radical-pilot-agent-multicore.py
    src/radical/pilot/bootstrapper/default_bootstrapper.sh
    src/radical/pilot/compute_unit_description.py
    src/radical/pilot/controller/input_file_transfer_worker.py
    src/radical/pilot/controller/output_file_transfer_worker.py