- update nmap to version 6.25
- fix build with clang and stdlib=libc++ 
Nmap 6.25 [2012-11-29]
o [NSE] Added CPE to smb-os-discovery output.
o [Ncat] Fixed the printing of warning messages for large arguments to
the -i and -w options. [Michal Hlavinka]
o [Ncat] Shut down the write part of connected sockets in listen mode
when stdin hits EOF, just as was already done in connect mode.
o [NSE] Added new fingerprints for http-enum: Sitecore, Moodle, typo3,
SquirrelMail, RoundCube. [Jesper Kuckelhahn]
o Added some new checks for failed library calls. [Bill Parker]
Submitted by: arrowdodger <email@example.com> 
Anders N. <firstname.lastname@example.org> (general update request)