Update rcairo to 1.14.1.

Release 1.14.1 (2014-12-23) Kouhei Sutou <kou@cozmixng.org>
===========================================================

Windows users must upgrade. Non Windows users doesn't need to
upgrade.

Improvements
------------

* Upgraded bundled libraries for Windows. libpng is upgraded to
  1.6.16 from 1.6.14. libpng 1.6.14 has vulnerability.

(obache)