SW-516: made generic fix for handling python2 <-> python3 subprocess output. Used that in cep4_utils.

SW-488: minor fixes, logging, and added a parameter 'min_nr_of_nodes' to get_cep4_available_cpu_nodes_sorted_ascending_by_load so we can always get at least a number of cpu nodes, even if they are under (too) heavy load

SW-540: moved ssh_cmd_list method into seperate module ssh_utils.py. Added module lcu_utils.py with wrappers around lcurun and the stations.txt file and fetching station calibration tables.

SW-0: moved the cep4_utils.py file from QA to LCS/PyCommon, and fixed references. Needs to be adapated in https://svn.astron.nl/LOFAR/branches/adder-Task10079 as well.

SW-0: another manual merge (manual file copy) from https://svn.astron.nl/LOFAR/branches/adder-Task10079

Task #10079: another manual merge (manual file copy) from https://svn.astron.nl/LOFAR/branches/adder-Task10079

SW-401: merged new QA_Service developments from trunk, which came via a manual merge (manual file copy) from https://svn.astron.nl/LOFAR/branches/adder-Task10079

SW-401: another manual merge (manual file copy) from https://svn.astron.nl/LOFAR/branches/adder-Task10079

Task #10079: manually copied parts of the QA package into LOFAR-Release-3_1. This allows us to roll out a new LOFAR-Release-3_1 on the scu with an extra QA_Service. The QA_Service hardly depends on anything, and doesn't require modifications to the rest of the lofar code. This makes this unusual manual merge acceptable. The rest of the QA code is not part of this release, and is not merged to this branch (yet). It runs isolated in docker containers on cep4.