fixes #6275 - idempotence needs clone of original data and to handle *_port
Fixes #6396: an error removing a DHCP record (record doesn't exist) stops the delete process for a host
Fixes #6412: Trying to remove a DHCP record fails due to an invalid subnet check
fixes #6583 - Use Enumerable#find instead of each where possible
fixes #6584 - Replace Kernel#open with File.open
fixes #6585 - Update Proxy::Util::CommandTask to handle Ruby 1.8 and 1.9+

In this update, use 'true' and 'false' to test $? return codes 0 and 1, respectively.
In Ruby 1.8.x, the return code from Open3.popen3 is always 0, some errors will not be caught.
First pass at DHCP API tests
Move dhcp configs into test/fixtures/dhcp/
Parse dhcp.conf test fixture instead of a stub
Tests for Proxy::Puppet::Runner
Tests for DHCP API route /:subnet/unused_ip

Set a consistent temp file location and clear it before each run.
Test for ISC DHCP included files