Improve ncd status logging

Fixes #12.

In addition, restore the original formatting of ncd status line in `/var/log/ncm-cdispd` to avoid breaking existing parser for this file (I know that line is parsed to raise attention when a component failed).

Still work in progress, would like to add the list of failed components as described in #12.
May be we should fix the documentation but for me (checked on my test system), there is a file left by ncm-ncd only for failed components (components with errors, not warning) and the file is removed after a succesful execution of the component.