Added FeatureCollection.enumerateProperties() (#62)

Sources/GISTools/Algorithms/EnumerateProperties.swift

@@ -0,0 +1,17 @@
+#if !os(Linux)
+import CoreLocation
+#endif
+import Foundation
+
+extension FeatureCollection {
+
+    /// Enumerate all properties in the FeatureCollection with feature index..
+    ///
+    /// - Parameter callback: The callback function
+    public func enumerateProperties(_ callback: (_ featureIndex: Int, _ properties: [String: Sendable]) -> Void)  {
+        for (featureIndex, feature) in features.enumerated() {
+            callback(featureIndex, feature.properties)
+        }
+    }
+
+}