ifup: <match> recursive <child> generation
fsm: change ni_fsm_exists_applicable_policy param
fsm: check only given worker's name on <device>
fsm: cleanup of ni_fsm_policy_applicable()

- move common checks to the caller
- removed unnecessary debug messages
- cleanup comments
policy: add extra debug to ifcondition functions

NI_LOG_DEBUG2 lvelel needed to enable it.
ifcondition: Fix <child> handling

Handle <child> the same way as <and>.
Merge pull request #329 from pwieczorkiewicz/child_policy

nanny: make policy application mechanism aware of children dependency