Add string-input mode to vtkGeoJSONReader
Fix logic to read single Feature as well as FeatureCollection objects
Add "feature-id" data array to polydata produced by vtkGeoJSONReader

Array is vtkStringArray.
Removed case-insensitive logic for feature and geometry "type" comparisons.
Updated test to optionally write out vtk file
Also alphabetized the include lists.
Update GeoJSON reader to specify property data to be stored with polydata

Adds internal member to store list of GeoJSONPropertySpec instances
Functionality itself is todo
Generalize GeoJSON test and include json-schema input for properties

Add "ny points" test files (geometry & schema)
Parse feature properties input (GeoJSON) and apply to output (vtkPolyData)
Add vtkGeoJSONProperty class to simplify logic a bit.

Also take advantage of the fact the vtkVariant knows its data type.
Rename "defaultValue" --> "typeAndDefaultValue" to be more precise.
Merge branch 'master' into john/read-feature-properties
Pass Json::Value by reference & const where appropriate
Merge pull request #2 from OpenGeoscience/john/read-feature-properties

John/read feature properties