Too many files open from ARP cache service

[araspitzu]

Poor behavior of ArpService leaves too many files open causing:

java.io.FileNotFoundException: /proc/net/arp (Too many open files)
at java.io.FileInputStream.open0(Native Method)
at java.io.FileInputStream.open(FileInputStream.java:195)
at java.io.FileInputStream.(FileInputStream.java:138)
at scala.io.Source$.fromFile(Source.scala:91)
at scala.io.Source$.fromFile(Source.scala:76)
at scala.io.Source$.fromFile(Source.scala:54)
at iptables.ArpService$.arpLookup(ArpService.scala:33)
at resources.ExtraDirectives.$anonfun$extractClientMAC$3(CommonResource.scala:47)