Merge pull request #16 from dblodgett-usgs/master

1.6 done.
Merge pull request #17 from dblodgett-usgs/master

4.2.1-18
Renamed "aid spec to aide to match cookbook name. Added a dependency on chefspec/berkshelf in our spec_helper. This allows us to automatically download cookbook dependencies when running rspec. This solved my auditd cookbook dependency issue. More info here: https://github.com/sethvargo/chefspec#berkshelf
Added knife-spec to Gemfile

Added to take advantage of spec auto generation, re: https://github.com/sethvargo/knife-spec
Covers 1.1.18 - 1.1.24

Also removed knife-spec from gemfile at cookbook level. Not needed.
Implements 3.3
Fix failing spec due to including wrong template.
Made grub password configuration idempotent
3.3 Disable Avahi Server
3.5 Remove DHCP Server
Implemented fix for 3.16

Also fixed boot settings task by converting to template
4.1.2 Disable Send Packet Redirects
4.2.2 Disable ICMP Redirect Acceptance
4.2.4 Log Suspicious Packets
4.2.7 Enable RFC-recommended Source Route Validation
4.4.1 Disable IPv6
Updated sysctl executions to also work with /sbin/sysctl
4.4.2.2 Disable IPv6 Redirect Acceptance
Added header info to files generted by chef
4.5.1 - 4.5.4