Filtering to make sure snmp values are complete

I have a switch that returns some interface stats without ifBytesOut,
which caused this script to blow up. Thus, a slightly clever filter that
makes sure every entry in snmpTable[*] contains all of the outValues
listed.
Adding 'graphiteName' parameter

I have hosts I have to address by FQDN, but I don't want the FQDN
hierarchy in graphite (thing -> mydomain -> com).  Trivial change to add a
vanity name of the user's choosing.