Refactor: Move classes to separate files with one-liner namespace style

X86Disassembler/PE/OptionalHeader.cs

@@ -70,13 +70,4 @@ namespace X86Disassembler.PE
             return Magic == PE32PLUS_MAGIC;
         }
     }
-    
-    /// <summary>
-    /// Represents a data directory in the optional header
-    /// </summary>
-    public class DataDirectory
-    {
-        public uint VirtualAddress;   // RVA of the table
-        public uint Size;             // Size of the table
-    }
 }