feat: update BMap bindings

- add testbench file in BMap bindings.
- reorganise BMap bindings code.
- write some BMapSharp binding code.

BMapBindings/BMapSharp/BMapSharpTestbench/Program.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace BMapSharpTestbench // Note: actual namespace depends on the project name.
+{
+    internal class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine("Hello World!");
+        }
+    }
+}