conntrack-tools: upgrade to 1.4.2

1. upgrade to 1.4.2
2. backport a patch to fix CVE-2015-6496:
   http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-6496



Signed-off-by: Roy Li <rongqing.li@windriver.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Joe MacDonald <joe_macdonald@mentor.com>