python render_with_detector: respect scale_factor and offsets - refs #2075
fix hit_test for lines + add tests - refs #2041
iwyu
Revert "geojson parser : support 'null' as valid coordinates property (empty geometry)"

Per GeoJSON spec :

```
A GeoJSON geometry object of any type other than "GeometryCollection" must have a member with the name "coordinates". The value of the coordinates member is always an array. The structure for the elements in this array is determined by the type of geometry.
```

This reverts commit f9ed2ce4e2d623c14df247db0025a549be29d75c.
cleanup commented out code
geojson generator : catch empty geometries early

```json
{"type":"Feature","id":1,"geometry":null,"properties":{}}
```
geojson parser : add phoenix v2 not_empty implementation
add tests for geojson empty/null geoms - #2083
apply 5eb406c7df to non PHOENIX_V3 code
Merge branch '2.3.x' of github.com:mapnik/mapnik
merge with branch 2.3.x
remove unused code
Merge branch 'master' of github.com:mapnik/mapnik into hb-prep
fix merge cruft with GRID_RENDERER define