GeoZero Shapefile driver

Reading Shapefiles with GeoZero API.

Features: - [x] Read support for OGC simple feature types - [x] Convert to GeoJSON, WKB (PostGIS/GeoPackage), WKT, GEOS, GDAL formats and more - [ ] Support for Multipatch types - [ ] Read spatial index - [ ] Read projection files

For writing Shapefiles either use shapefile-rs or the GDAL driver of GeoZero Core

Originally based on shapefile-rs from Thomas Montaigu.

Usage example

```Rust use geozero_core::geojson::GeoJsonWriter;

let reader = geozeroshp::Reader::frompath("poly.shp")?; let mut json: Vec = Vec::new(); let cnt = reader.iter_features(GeoJsonWriter::new(&mut json))?.count(); ```