Render fast subpixel halos.
Update reference image.
More tests.
Updated reference images.
scons: disable special handling of agg test, uneeded except for specific dev
remove geos plugin (moved to https://github.com/mapnik/non-core-plugins) - refs #1809
+ backport image_reader from buffer/string from image-readers-c++11 branch
+ fix warnings when compiling with g++ 4.2.1 on os x
update expected map-request image - seems valid, not sure when/what changed
Merge pull request #1781 from mapnik/subpixelhalo

Render halos < 1.0 with fast halo algorithm.