Release 0.5.1
=============

  * svg: implement overflow, viewBox and preserveAspectRatio for <symbol> (Emmanuel)
  * svg: fix a crash in blur filter in case of a null input surface (Emmanuel
  * svg: <feColorMatrix> support
  * svg: <feImage> support
  * svg: <feMorphology> support
  * svg: <feConvolveMatrix> support
  * svg: <feTurbulence> support
  * svg: <feDisplacementMap> support
  * svg: use Mario Klingeman's stackblur algorithm for <feBlur>
  * mathml: negative spacing constant support (Garen)
  * mathml: minlabelspacing support for <mlabeledtr> (Garen)
  * introspection: better python support (Emmanuel)
  * cairo: avoid integer oveflow (RyuzakiKK)
  * build: OSX compilation fix (Garen)
  * translation updates (Мирослав, Aurimas, Balázs, Piotr, Tom, Anders, Daniel, Andika, Marek, Pedro, Duarte, Cédric, Samir, Serdar, Ask, Milo, Rūdolfs, Nathan, Matej, Fabio, Aron, Mario, Rafael, Andika)