Log Message:
Import libbpg-0.9.4 as wip/libbpg.

TODO:
* rpath for bpgenc/bpgdec missing
* library not installed
* library not libtoolized

Problems reported upstream, hoping for upstream fix.
-- wiz 20150110

BPG (Better Portable Graphics) is a new image format. Its purpose
is to replace the JPEG image format when quality or file size is
an issue. Its main advantages are:

  * High compression ratio. Files are much smaller than JPEG for
  similar quality.
  * Supported by most Web browsers with a small Javascript decoder
  * Based on a subset of the HEVC open video compression standard.
  * Supports the same chroma formats as JPEG (grayscale, YCbCr
  4:2:0, 4:2:2, 4:4:4) to reduce the losses during the conversion.
  An alpha channel is supported. The RGB, YCgCo and CMYK color
  spaces are also supported.
  * Native support of 8 to 14 bits per channel for a higher dynamic
  range.
  * Lossless compression is supported.
  * Various metadata (such as EXIF, ICC profile, XMP) can be
  included.