• Changed secure download site from https://linuxnet.ca/ieee/oui.txt (link down) to https://standards-oui.ieee.org in update-oui-database.sh
  script.
• Fixed segfault when HOME env is not set. Thanks to Till Zimmermann tzimmermann@uos.de.
• Use unsigned int for data_counter.hosts. Thanks to Brendan Coles bcoles@gmail.com
• Updated OUI table.