Fixed test_linux_dhcp.py broken from previous check in.

The broken tests include,
  test_output_opts_file
  test_reload_allocations
  test_reload_allocations_stale_pid

Code merged from icehouse commit 3f10716719454cf42eba618aca14f1c9df68822f.

Partial-rally-bug: DE701
Implements: rally-task TA3473
Not-in-upstream: false
Bump min required version for dnsmasq to 2.63

This patch bumps the min version requirement from 2.59 to 2.63
for dnsmasq which is needed to use multiple tags for dual stack IPv4/6.

Closes-bug: 1233339
Closes-rally-bug: DE701
Upstream-Review: https://review.openstack.org/105378
Not-in-upstream: false
Merge pull request #15 from CiscoSystems/de701

De701