Log Message:
Update to 0.1.56

Changelog:
2018-08-14 babl-0.1.56
Improvements to the caching of profiled conversion chains between invocations
by ignoring unknown bits in cache file and remember which conversions yielded
reference fishes.

2018-07-23 babl-0.1.54
Export babl_space_get_icc, babl_space_get, babl_model_with_space,
babl_space_with_trc, babl_format_get_encoding, babl_model_is, SSE2 versions of
YA float and Y float to CIE L float.