[CALCITE-5262] Add many spatial functions, including support for WKB …

…(well-known binary) and GeoJSON

Add functions:
 * ST_AsBinary
 * ST_AsEWKT and ST_GeomFromEWKT
 * ST_AsGeoJSON and ST_GeomFromGeoJSON
 * ST_AsGML and ST_GeomFromGML
 * ST_AsWKB and ST_GeomFromWKB
 * ST_Centroid
 * ST_ConvexHull
 * ST_CoordDim
 * ST_Covers
 * ST_Difference and ST_SymDifference
 * ST_Dimension and ST_BoundingCircle
 * ST_Expand
 * ST_Extent
 * ST_ExteriorRing and ST_InteriorRing
 * ST_Force2D and ST_Force3D
 * ST_GeometryN
 * ST_Intersection
 * ST_IsClosed, ST_IsRectangle, ST_IsRing, ST_IsSimple, ST_IsValid, ST_IsEmpty
 * ST_LineMerge
 * ST_MakeEllipse and ST_MakePolygon
 * ST_MakeValid
 * ST_MinimumDiameter
 * ST_MinimumRectangle
 * ST_NumGeometries
 * ST_NumInteriorRing and ST_NumInteriorRings
 * ST_NumPoints
 * ST_OctagonalEnvelope
 * ST_PointN
 * ST_PointOnSurface
 * ST_Polygonize
 * ST_PrecisionReducer
 * ST_Relate
 * ST_Rotate
 * ST_Scale
 * ST_Simplify and ST_SimplifyPreserveTopology
 * ST_Snap
 * ST_SRID
 * ST_StartPoint and ST_EndPoint
 * ST_ToMultiLine and ST_ToMultiSegments
 * ST_ToMultiPoint
 * ST_Translate
 * ST_XMax, ST_XMin, ST_YMax, ST_YMin, ST_ZMin, ST_ZMax

Improve documentation, aliases, and variable names.

Set the extractOnlyPolygonal option to true in ST_Polygonize.

Replace Esri by JTS in the acknowledgements.

Close #2893

core/src/main/java/org/apache/calcite/runtime/CoordinateTransformer.java

@@ -0,0 +1,51 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.runtime;
+
+import org.locationtech.jts.geom.Coordinate;
+import org.locationtech.jts.geom.CoordinateSequence;
+import org.locationtech.jts.geom.Geometry;
+import org.locationtech.jts.geom.impl.CoordinateArraySequence;
+import org.locationtech.jts.geom.util.GeometryTransformer;
+
+import java.util.function.Function;
+import java.util.stream.Stream;
+
+/**
+ * Transforms the coordinates of a geometry.
+ */
+public class CoordinateTransformer extends GeometryTransformer {
+
+  private final Function<Coordinate, Coordinate> transform;
+
+  /**
+   * Creates a transformer that applies the {@code transform} to all coordinates.
+   */
+  public CoordinateTransformer(Function<Coordinate, Coordinate> transform) {
+    this.transform = transform;
+  }
+
+  @Override protected CoordinateSequence transformCoordinates(
+      CoordinateSequence coordinateSequence, Geometry parent) {
+    Coordinate[] coordinateArray =
+        Stream.of(coordinateSequence.toCoordinateArray())
+            .map(transform)
+            .toArray(Coordinate[]::new);
+    return new CoordinateArraySequence(coordinateArray);
+  }
+
+}