#3 Fix system file locations

[Allan Beaufour Larsen]

The location of the system files are not correct.
Some are in /etc, some in ~/.netdj/ etc.

Should be user or system-wide installation:
- state in /var/state or ~/.netdj/state
- log in /var/log/ or /.netdj/log
- playlog in /var/log? og ~/.netdj/playlog