Change the default graphite namespace.

per_ten for 10 seconds, to match the graphite push frequency.
Allow dashes in graphite names.
Better option parsing failure messages.
Show the lock file name alongside the pid.
Use the passed-in config.
Make config destroy non-global.
Comment tweak.
Separate config validity checking of options and addresses.

Needed because some parts may be coming from command line.
Reconfig the argv only if there is new argc.

(in this context argv = the listen and forwarding addresses)

If there's no new argv, keep the old ones.  This may happen if
the addresses were given in the command line, and there are no
addresses in the config file.
The freeing is conditional.