* Fix problem with metrics when ping return Destination net unreachable
Add test case TestUnreachablePingGather
Add percent_reply_loss
Fix some other tests
* Add errors measurment
* fir problem with ping reply "TTL expired in transit" ( use regex for more specific condition - TTL in line but it's a not valid replay )
add test case for "TTL expired in transit" - TestTTLExpiredPingGather