new file:   arch-pcap.sh
	modified:   install-prereqs.sh
	modified:   install-tools.sh

wash doesn't seem to work with the new libpcap on arch linux.
Theres a new script to downgrade libpcap to 1.4.0.
	modified:   install-prereqs.sh
	modified:   arch-pcap.sh
	modified:   install-prereqs.sh

Fixed some bugs in the new script and the old one.