anchor.diff:  /// Parameter 2: fileName - The fileName of the zip file.
   let Unzip target fileName =  
       let zip = new FastZip()
  -    zip.ExtractZip (fileName, target, "")
  -    +    zip.ExtractZip (fileName, target, "")
positive.code: module Fake.ZipHelper
  
  open System.IO
  open ICSharpCode.SharpZipLib.Checksums
  open ICSharpCode.SharpZipLib.Zip
  open System.Globalization
  open System
  open ICSharpCode.SharpZipLib
  
  /// The default zip level
  let DefaultZipLevel = 6
  
  /// Creates a zip file with the given files
  let CreateZip workingDir fileName comment level flatten files =
    let crc = new Crc32()
    let workingDir =
      let dir = new DirectoryInfo(workingDir)
      if not dir.Exists then failwithf "Directory not found: %s" dir.FullName
  
negative.code:       let itemSpec = ZipEntry.CleanName(itemSpec)
        let entry = new ZipEntry(itemSpec)
        entry.DateTime <- info.LastWriteTime
        entry.Size <- info.Length
        
        use stream2 = info.OpenRead()
  
        stream.PutNextEntry(entry)
        let length = ref stream2.Length
        stream2.Seek(0L, SeekOrigin.Begin) |> ignore
        while !length > 0L do
          let count = stream2.Read(buffer, 0, buffer.Length)
          stream.Write(buffer, 0, count)
          length := !length - (int64 count)
        
        logfn "File added %s" itemSpec
        
    stream.Finish()
    tracefn "Zip successfully created %s" fileName
   
  /// Creates a zip file with the given files 
  ///
  