Automatic detection of the system configuration

[Blanca-Fuentes]

This PR introduces the option of detecting the system configuration automatically and writing the corresponding ReFrame config file.

• The system's partitions are created based on the node features detected with Slurm .
• It is only implemented for Slurm
• ReFrame must be run with the new action option: reframe --detect-configuration=autodetect_config.py (an example of the autodetect_config.py is included). In the detect_config() the optional arguments are

1. detect_containers: submits jobs to each partition to detect container platforms
2. sched_options: additional scheduler access options that must be included for all partitions
3. time_limit: time limit for the remote detection jobs (container platforms)
4. exclude_feats: node features to be ignored in the filtering of the nodes to determine the partitions, patterns like row* are accepted
5. filename: name of the configuration file that will be generated

• For the job submissions, a shared directory with the compute nodes must/can be specified using the RFM_REMOTE_WORKDIR

Ideas/todo's

• Move the detection of container platforms in the remote partitions to --detect-topology
• Combine the configuration detection with reframe --detect-topology
• Fix tests
• Add documentation
• Add unit tests