avoid a few uneeded copies
rollback to copying bbox member of filter_in_box - previous change led to odd node-mapnik shapefile query failure
add visual tests for group-by feature - refs #916
fix initialization of hue and sat in rgb2hsl + fix rounding in hsl2rgb to be stable on 32 bit systems (no change on 64 bit) - refs #1954
add test data as followup to 87a2787a407003f1328a4b0a38692d372a257c22 - refs #916
renable hsla filter as 'scale-hsla' - refs #1954
disable failing test of #1913 for now
webp encoding/decoding support - refs #1955
update changelog after #1955
ensure agg rendering buffer uses proper dimensions since these may become more dynamic in the near future - refs #1478
Merge branch 'master' into skia-renderer
+ text rendering work-in-progress