Add Python script for generating Natvis file and update file for 3.11.2 (#3697)

tools/generate_natvis/README.md

@@ -0,0 +1,10 @@
+generate_natvis.py
+==================
+
+Generate the Natvis debugger visualization file for all supported namespace combinations.
+
+## Usage
+
+```
+./generate_natvis.py --version X.Y.Z output_directory/
+```