Updated SharpZipLib to a hand-built bugfixed copy.

Uses the patch from icsharpcode/SharpZipLib#53 .
Thank you, @Novn, for writing this.

Uses the build fixes from https://github.com/Arakis/SharpZipLib for
Mono. Thank you, @arakis, for providing these.

The branch I built from is at
https://github.com/pjf/SharpZipLib/tree/ckan_gh221

Attentioning @bastianeicher who is maintaining a totally awesome
SharpZipLib patches branch. @Novn's patch above fixes the bug
described at http://community.sharpdevelop.net/forums/t/21758.aspx .
There's a test file at
https://github.com/pjf/CKAN/blob/221_ziplib/t/data/gh221.zip which shows
the presence of the bug when combined with the test at
https://github.com/pjf/CKAN/blob/221_ziplib/CKAN/Tests/ZipLib.cs .

Closes #221.
Closes KSP-CKAN/CKAN-meta#33

@malahx: I'll be releasing an updated CKAN client shortly with these
fixes.

NetKAN.csproj

@@ -33,7 +33,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="ICSharpCode.SharpZipLib">
-      <HintPath>..\packages\SharpZipLib.0.86.0\lib\20\ICSharpCode.SharpZipLib.dll</HintPath>
+      <HintPath>..\packages\SharpZipLib.0.86.0-pjf-ckan_gh221\ICSharpCode.SharpZipLib.dll</HintPath>
     </Reference>
     <Reference Include="System" />
     <Reference Include="Newtonsoft.Json">