* Added ability to specify number of pings to be transmitted
* Abstracted ping logic to return "percent of pings requests not responded". The logic was not reworked,
and stayed the same for now... (could be reworked, but currently out of scope for current need).
* Added wrapper functions to return different information:
ping() - returns True/False --> Same as original ping() command (for backwards compatability)
ping_percent_loss() --> Returns percent of (missing replies)/requests
ping_percent_success() --> Returns percent of (received replies)/requests
Change-Id: If242fd02dde3642372c6c5e1f3e117a38e51c1d7
333812211a