Fixed some CA violations.

NTwain/NativeMethods.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Text;
+
+namespace NTwain
+{
+    static class NativeMethods
+    {
+        // should be unsafe native methods?
+
+        #region mem stuff for twain 1.x
+
+        [DllImport("kernel32", SetLastError = true, EntryPoint = "GlobalAlloc")]
+        internal static extern IntPtr WinGlobalAlloc(uint uFlags, UIntPtr dwBytes);
+
+        [DllImport("kernel32", SetLastError = true, EntryPoint = "GlobalFree")]
+        internal static extern IntPtr WinGlobalFree(IntPtr hMem);
+
+        [DllImport("kernel32", SetLastError = true, EntryPoint = "GlobalLock")]
+        internal static extern IntPtr WinGlobalLock(IntPtr handle);
+
+        [DllImport("kernel32", SetLastError = true, EntryPoint = "GlobalUnlock")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static extern bool WinGlobalUnlock(IntPtr handle);
+
+        #endregion
+    }
+}