Extra diags for when chronos hangs
Make extra_diags executable
Allow monit to run 2 commands when chronos hangs
Rename extra_diags to write_monit_restart_diags (to clarify this is not part of clearwater-diags-monitor)
Merge pull request #56 from Metaswitch/extra_diags

[Reviewer: Andy][From: Alex] Get useful diags when chronos hangs and is restarted by monit