Update the changelog for the upcoming 0.1.4 release

ChangeLog

+0.1.4
+ - Updated upstream sources, with minor changes to the decoder API
+   breaking the ABI. (Calling code using AUDIO_CHANNEL_TYPE may need to
+   be updated. A new option AAC_PCM_LIMITER_ENABLE has been added, enabled
+   by default, which incurs extra decoding delay.)
+ - PowerPC optimizations, fixes for building on AIX
+ - Support for reading streamed wav files in the encoder example
+ - Fix VBR encoding of sample rates over 64 kHz
+
 0.1.3
  - Updated upstream sources, with a number of crash fixes and new features
    (including support for encoding 7.1)