remove unused color cache code
first stab at webp support
test cases for webp encoding
use advanced api to stream into file handle
reencoding benchmarks
travis ci: add webp module
use dev package for building on travis
make it work with old libwebp
add build products to ignore
add webp decoding
update benchmark
we now allow level 0 (no compression) too
fix at least some of the failures on travis
use Mean average error metric when comparing
mark a few jpegs as very similar rather than identical
mark more images as similar
Update CHANGELOG/README.
Merge pull request #29 from developmentseed/webp

WebP support
0.8.0
search for homebrew provided jpeg-turbo on OS X - refs #32