Add PE skeleton, change MZ stubs

BurnOutSharp.Models/PortableExecutable/Executable.cs

@@ -0,0 +1,17 @@
+namespace BurnOutSharp.Models.PortableExecutable
+{
+    /// <summary>
+    /// The following list describes the Microsoft PE executable format, with the
+    /// base of the image header at the top. The section from the MS-DOS 2.0
+    /// Compatible EXE Header through to the unused section just before the PE header
+    /// is the MS-DOS 2.0 Section, and is used for MS-DOS compatibility only.
+    /// </summary>
+    /// <see href="https://learn.microsoft.com/en-us/windows/win32/debug/pe-format"/>
+    public class Executable
+    {
+        /// <summary>
+        /// MS-DOS executable stub
+        /// </summary>
+        public MSDOS.Executable Stub { get; set; }
+    }
+}