VCL-1089 - Change ping module to use Net::Ping::External

-applied patch submitted by Mike Jennings that changes utils.pm
_pingnode function to use Net::Ping::External rather than Net::Ping so
that vcld doesn't require root level rights
-moved "use Net::Ping::External qw(ping);" line to top of file with other
calls to "use"
-updated description of _pingnode function
2 files changed