Log Message:
Update to 1.4.0

Changelog:
2015-04-03 v1.4.0 "Indian Runner Duck"
  This release includes significant improvements to the VP9 codec.

  - Upgrading:
    This release is ABI incompatible with 1.3.0. It drops the compatibility
    layer, requiring VPX_IMG_FMT_* instead of IMG_FMT_*, and adds several codec
    controls for VP9.

  - Enhancements:
    Faster VP9 encoding and decoding
    Multithreaded VP9 decoding (tile and frame-based)
    Multithreaded VP9 encoding - on by default
    YUV 4:2:2 and 4:4:4 support in VP9
    10 and 12bit support in VP9
    64bit ARM support by replacing ARM assembly with intrinsics

  - Bug Fixes:
    Fixes a VP9 bitstream issue in Profile 1. This only affected non-YUV 4:2:0
    files.

  - Known Issues:
    Frame Parallel decoding fails for segmented and non-420 files.