Increase the count of ping probes

It's allowed now to get at least 3 answers for no more than 10 requests.
Interval between connectivity checks is increaced (30 -> 60 sec).

Closes-Bug: #1322102

Change-Id: I0b227e3426c3d8b453986e6545829a11e125ce0b
(cherry picked from commit baf2746d5867c9e8fe58b743e451518c4c107590)
Merge "Increase the count of ping probes" into stable/4.1