Fixed Sec Bug #67717 segfault in dns_get_record CVE-2014-3597

Incomplete fix for CVE-2014-4049

Check possible buffer overflow
- pass real buffer end to dn_expand calls
- check buffer len before each read
NEWS
Merge branch 'PHP-5.4' into PHP-5.5

* PHP-5.4:
  NEWS
  Fixed Sec Bug #67717 segfault in dns_get_record CVE-2014-3597
NEWS