Log Message:
Update to 0.6.1

Changelog:
libwebp-0.6.1
- 11/24/2017: version 0.6.1
  This is a binary compatible release.
  * lossless performance and compression improvements + a new 'cruncher' mode
    (-m 6 -q 100)
  * ARM performance improvements with clang (15-20% w/ndk r15c, issue #339)
  * webp-js: emscripten/webassembly based javascript decoder
  * miscellaneous bug & build fixes (issue #329, #332, #343, #353, #360, #361,
    #363)
  Tool updates / additions:
    added webpinfo - prints file format information (issue #330)
    gif2webp - loop behavior modified to match Chrome M63+ (crbug.com/649264);
               '-loop_compatibility' can be used for the old behavior