Fix ncm-cdispd forgetting about failed configuration modules

- Fix function used to run ncm-ncd not returning ncm-ncd status
- Use `CAF::Process` to execute ncm-ncd
- Properly retrieve ncm-ncd status (fix for the buggy value that has
always been returned)
- Improve debug logging

Fixes #4
I don't think so. The need to shift right $? is due to system() call, not CAF::Process itself. Check perl doc about this. Not shifting it has been the reason for the famous 65xxx return code from `ncm-ncd`.