Update to 2.1.5:

Changes between 2.1.4 and 2.1.5:
--------------------------------

Core:
 * Fix compilation on OS/2

Access:
 * Stability improvements for the QTSound capture module

Mac OS X audio output:
 * Fix channel ordering
 * Increase the buffersize

Decoders:
 * Fix DxVA2 decoding of samples needing more surfaces
 * Improve MAD resistance to broken mp3 streams
 * Fix PGS alignment in MKV

Qt Interface:
 * Don't rename mp3 converted files to .raw

Mac OS X Interface:
 * Correctly support video-on-top
 * Fix video output event propagation on Macs with retina displays
 * Stability improvements when using future VLC releases side by side

Streaming:
 * Fix transcode when audio format changes

Security contents:
 * Updated GnuTLS to 3.1.25 (CVE-2014-3466)
 * Updated libpng to 1.6.10 (CVE-2014-0333)

Translations:
 * Update British English