Update opera to 12.13.

Opera 12.13 is a recommended upgrade offering security and stability
enhancements.

Fixes and Stability Enhancements since Opera 12.12
General and User Interface
  * Fixed an issue where Opera gets internal communication errors on Facebook
  * Fixed an issue where no webpages load on startup, if Opera is disconnected
    from the Internet
  * Fixed an issue where images will not load after back navigation, when a site
    uses the HTML5 history API (deviantart.com)
    Linux and Windows
      * A new stand-alone update-checker, as part of a planned upgrade of the
auto-update system
    Windows
      * Improved protection against hijacking of the default search, including
a one-time reset
Security
  * Fixed an issue where DOM events manipulation might be used to execute
    arbitrary code, as reported by Arthur Gerkis; see our advisory:
      http://www.opera.com/support/kb/view/1042/
  * Fixed an issue where use of SVG clipPaths could allow execution of arbitrary
    code, as reported by anonymous via the iSIGHT Partners GVP Program; see our
    advisory:
      http://www.opera.com/support/kb/view/1043/
  * Fixed a low severity security issue; details will be disclosed at a later
    date
  * Fixed an issue where CORS requests could omit the preflight request, as
    reported by webpentest; see our advisory:
      http://www.opera.com/support/kb/view/1045/

(obache)