Modified AESGCM to support specifying the block cipher engine through generics

mRemoteNGTests/Security/AesGcmTests.cs

@@ -1,6 +1,7 @@
 using System.Security;
 using mRemoteNG.Security;
 using NUnit.Framework;
+using Org.BouncyCastle.Crypto.Engines;
 
 
 namespace mRemoteNGTests.Security
@@ -14,7 +15,7 @@ namespace mRemoteNGTests.Security
         [SetUp]
         public void Setup()
         {
-            _aesgcm = new AESGCM();
+            _aesgcm = new AESGCM<AesFastEngine>();
             _encryptionKey = "mypassword111111".ConvertToSecureString();
             _plainText = "MySecret!";
         }