Merge branch 'cylc_config_-_add_--platform-names' of github.com:wxtim…

…/cylc into cylc_config_-_add_--platform-names

* 'cylc_config_-_add_--platform-names' of github.com:wxtim/cylc:
  Apply suggestions from code review
  response to review
  Update cylc/flow/scripts/config.py
  refactor testing
  Apply suggestions from code review
  Update cylc/flow/scripts/config.py
  created cylc config --platform-names and --platform-meta options; Moved tests/cylc-get-config to tests/cylc-config