fix #297

Author: yanghuan

CSharp.lua/CoreSystem.Lua/CoreSystem/IO/File.lua

@@ -70,7 +70,7 @@ define("System.IO.File", {
     end
     return System.arrayFromTable(t, System.String)
   end,  
-  WriteWriteAllBytes = function (path, contents)
+  WriteAllBytes = function (path, contents)
     writeAll(path, contents, "wb")
   end,
   WriteAllText = function (path, contents)
@@ -100,4 +100,4 @@ define("System.IO.File", {
   end
 })
 
-end
+end