Update to 3.1.0 (approved by tonnerre@)
Note that this now requires php for the web interface.

Changes since 3.0.3:
- lots of bug fixes, including security fixes for CVE-2008-5027,
  CVE-2008-5028, and CVE-2008-6373 (secunia.com SA32909)
- Sample audio files for CGIs removed from distribution
- Added documentation on CGI security issues
-�Better out-of-disk-space error handling when writing retention and
  status files
- Disabled adaptive check and eventhandler commands for security reasons
- Added wildcard host matching in CGIs
- Added support for x509 cert authentication in the CGIs
- Updates to nagiostats utility for faster execution if using external
  stats file
- Added a bit more verbosity to config verification

(bouyer)