Merge branch 'master' of https://github.com/sshnet/Cryptography.git

Author: drieseng

test/SshNet.Security.Cryptography.Shared.Tests/HMACMD5Test.cs

@@ -1,4 +1,5 @@
-using System.Text;
+using System;
+using System.Text;
 using SshNet.Security.Cryptography.Common.Tests;
 using Xunit;