Merge pull request #394 from olafhering/olh-misc

DHCP4 changes (bnc#866994)
nanny: reset worker on enable(), disable()

rearming is not enough as often reseting internal fsm
is mandatory.
nanny: arm nanny only if ni_config_use_nanny() is true

Nanny is still allowed to start in order not to freak out
systemd, but does not register any signals nor performs
any actions.
debugging: lowered timer debug messages to debug2
Merge pull request #395 from mtomaschewski/timer-debug

debugging: lowered timer debug messages to debug2
debugging: fixed last commit to use right arg order
Merge branch 'master' into testing
Merge pull request #396 from pwieczorkiewicz/nanny-reset