validator-core - curved geometries - allows to keep curved geometries in normalized data

[mborne]

Problem

Currently, CURVEDPOLYGON are linearized to POLYGON in normalized data.

Actions

• Ensure that datastore components (postgis, geoserver,...) supports curved geometries
• Add an option --no-linearization to use WKTWriter2 instead of WKTWriter which converts curve geometries to linear geometries.

(see #232)