use underscore convention for driver code

the raster subpackage has used an underscore to denote file format
drivers

this applies that convention to the vector subpackage for more
consistency

karta/vector/__init__.py

@@ -9,20 +9,21 @@
 numbers.Integral.register(numpy.integer)
 
 from . import geometry
-from . import table
-from . import geojson
-from . import gpx
 from . import quadtree
 from . import rtree
+from . import table
+from . import _geojson as geojson
+from . import _gpx as gpx
+from . import _shp as shp
 #from . import redblack
 
 from .geometry import (Geometry, Point, Line, Polygon,
                        Multipoint, Multiline, Multipolygon,
                        multipart_from_singleparts)
 from .read import (from_shape, read_geojson, read_shapefile,
                    read_gpx_waypts, read_gpx_tracks)
-from .shp import write_shapefile
 from .table import Table
+from ._shp import write_shapefile
 
 __all__ = ["geometry", "geojson", "gpx",
            "Point", "Line", "Polygon",

karta/vector/geometry.py

@@ -11,8 +11,8 @@
 import numbers
 import numpy as np
 from .decorators import cache_decorator
-from .geojson import GeoJSONOutMixin
-from .shp import ShapefileOutMixin
+from ._geojson import GeoJSONOutMixin
+from ._shp import ShapefileOutMixin
 from .table import Table, Indexer
 from .utilities import _reproject, _reproject_nested, _flatten, _as_nested_lists
 from .coordstring import CoordString

karta/vector/read.py

@@ -7,9 +7,9 @@
 from numbers import Number
 from osgeo import ogr
 from . import geometry
-from . import geojson
-from . import shp
-from . import gpx
+from . import _geojson as geojson
+from . import _shp as shp
+from . import _gpx as gpx
 from ..crs import GeographicalCRS, ProjectedCRS, LonLatWGS84
 from .. import errors
 

tests/geojson_tests.py

@@ -10,8 +10,8 @@
 from test_helper import TESTDATA
 
 import karta.vector as vector
-import karta.vector.geojson as geojson
-from karta.vector.geojson import GeoJSONReader, GeoJSONNamedCRS
+import karta.vector._geojson as geojson
+from karta.vector._geojson import GeoJSONReader, GeoJSONNamedCRS
 from karta.vector.geometry import Point, Line, Polygon, Multipoint, Multiline, Multipolygon
 from karta.crs import LonLatWGS84, WebMercator, Cartesian