Fixed compiler warnings
diff --git a/src/Lucene.Net.Benchmark/Support/TagSoup/HTMLScanner.cs b/src/Lucene.Net.Benchmark/Support/TagSoup/HTMLScanner.cs
index 62833ae..54e3f1d 100644
--- a/src/Lucene.Net.Benchmark/Support/TagSoup/HTMLScanner.cs
+++ b/src/Lucene.Net.Benchmark/Support/TagSoup/HTMLScanner.cs
@@ -1,4 +1,4 @@
-// This file is part of TagSoup and is Copyright 2002-2008 by John Cowan.
+// This file is part of TagSoup and is Copyright 2002-2008 by John Cowan.
 //
 // TagSoup is licensed under the Apache License,
 // Version 2.0.  You may obtain a copy of this license at
@@ -17,6 +17,7 @@
 using System;
 using System.Globalization;
 using System.IO;
+using System.Text;
 
 namespace TagSoup
 {
@@ -716,19 +717,20 @@
             theOutputBuffer[theSize++] = (char)ch;
         }
 
-        /**
-        Test procedure.  Reads HTML from the standard input and writes
-        PYX to the standard output.
-        */
-
-        //	public static void main(string[] argv) {
-        //		IScanner s = new HTMLScanner();
-        //		TextReader r = new StreamReader(System.in, "UTF-8");
-        //		TextWriter w = new StreamWriter(System.out, "UTF-8");
-        //		PYXWriter pw = new PYXWriter(w);
-        //		s.scan(r, pw);
-        //		w.close();
-        //		}
+        ///// <summary>
+        ///// Test procedure.  Reads HTML from the standard input and writes
+        ///// PYX to the standard output.
+        ///// </summary>
+        ///// <param name="argv"></param>
+        //[System.Diagnostics.CodeAnalysis.SuppressMessage("Style", "IDE0060:Remove unused parameter", Justification = "Optional argument")]
+        //public static void Main(string[] argv)
+        //{
+        //    IScanner s = new HTMLScanner();
+        //    TextReader r = Console.In;
+        //    TextWriter w = Console.Out;
+        //    PYXWriter pw = new PYXWriter(w);
+        //    s.Scan(r, pw);
+        //}
 
 
         //private static string NiceChar(int value) // LUCENENET: IDE0051: Remove unused private member
diff --git a/src/Lucene.Net.Tests.Suggest/Spell/TestLuceneDictionary.cs b/src/Lucene.Net.Tests.Suggest/Spell/TestLuceneDictionary.cs
index df48dfe..ba4b0dd 100644
--- a/src/Lucene.Net.Tests.Suggest/Spell/TestLuceneDictionary.cs
+++ b/src/Lucene.Net.Tests.Suggest/Spell/TestLuceneDictionary.cs
@@ -1,4 +1,4 @@
-using Lucene.Net.Analysis;
+using Lucene.Net.Analysis;
 using Lucene.Net.Attributes;
 using Lucene.Net.Documents;
 using Lucene.Net.Index;
@@ -37,9 +37,7 @@
 
         private IndexReader indexReader = null;
         private LuceneDictionary ld;
-#pragma warning disable CS0618 // Type or member is obsolete
-        private IBytesRefIterator it;
-#pragma warning restore CS0618 // Type or member is obsolete
+        private IBytesRefEnumerator it;
         private BytesRef spare = new BytesRef();
 
 
@@ -86,7 +84,6 @@
         [Test]
         public void TestFieldNonExistent()
         {
-            IBytesRefEnumerator it;
             try
             {
                 indexReader = DirectoryReader.Open(store);
@@ -105,7 +102,6 @@
         [Test]
         public void TestFieldAaa()
         {
-            IBytesRefEnumerator it;
             try
             {
                 indexReader = DirectoryReader.Open(store);
@@ -125,7 +121,6 @@
         [Test]
         public void TestFieldContents_1()
         {
-            IBytesRefEnumerator it;
             try
             {
                 indexReader = DirectoryReader.Open(store);
@@ -159,7 +154,6 @@
         [Test]
         public void TestFieldContents_2()
         {
-            IBytesRefEnumerator it;
             try
             {
                 indexReader = DirectoryReader.Open(store);
@@ -183,7 +177,6 @@
         [Test]
         public void TestFieldZzz()
         {
-            IBytesRefEnumerator it;
             try
             {
                 indexReader = DirectoryReader.Open(store);
diff --git a/src/Lucene.Net.Tests/Index/TestPersistentSnapshotDeletionPolicy.cs b/src/Lucene.Net.Tests/Index/TestPersistentSnapshotDeletionPolicy.cs
index d5fcc54..1808768 100644
--- a/src/Lucene.Net.Tests/Index/TestPersistentSnapshotDeletionPolicy.cs
+++ b/src/Lucene.Net.Tests/Index/TestPersistentSnapshotDeletionPolicy.cs
@@ -144,7 +144,7 @@
                 }
                 else
                 {
-                    throw ioe;
+                    throw; // LUCENENET: CA2200: Rethrow to preserve stack details
                 }
             }
             Assert.AreEqual(0, psdp.SnapshotCount);
diff --git a/src/Lucene.Net.Tests/Support/TestOldPatches.cs b/src/Lucene.Net.Tests/Support/TestOldPatches.cs
index ab5b0cb..26b9c38 100644
--- a/src/Lucene.Net.Tests/Support/TestOldPatches.cs
+++ b/src/Lucene.Net.Tests/Support/TestOldPatches.cs
@@ -63,12 +63,13 @@
             //now serialize it 
             System.Runtime.Serialization.Formatters.Binary.BinaryFormatter serializer = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
             System.IO.MemoryStream memoryStream = new System.IO.MemoryStream();
+#pragma warning disable SYSLIB0011 // Type or member is obsolete (BinaryFormatter)
             serializer.Serialize(memoryStream, queryPreSerialized);
 
             //now deserialize 
             memoryStream.Seek(0, System.IO.SeekOrigin.Begin);
             Lucene.Net.Search.BooleanQuery queryPostSerialized = (Lucene.Net.Search.BooleanQuery)serializer.Deserialize(memoryStream);
-
+#pragma warning restore SYSLIB0011 // Type or member is obsolete (BinaryFormatter)
             memoryStream.Close();
 
             Assert.AreEqual(queryPreSerialized, queryPostSerialized, "See the issue: LUCENENET-170");
diff --git a/src/Lucene.Net.Tests/Support/TestSerialization.cs b/src/Lucene.Net.Tests/Support/TestSerialization.cs
index 5630a5a..a61e561 100644
--- a/src/Lucene.Net.Tests/Support/TestSerialization.cs
+++ b/src/Lucene.Net.Tests/Support/TestSerialization.cs
@@ -81,9 +81,11 @@
             
             System.Runtime.Serialization.Formatters.Binary.BinaryFormatter bf = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
             System.IO.MemoryStream ms = new System.IO.MemoryStream();
+#pragma warning disable SYSLIB0011 // Type or member is obsolete (BinaryFormatter)
             bf.Serialize(ms, lucQuery);
             ms.Seek(0, System.IO.SeekOrigin.Begin);
             Lucene.Net.Search.BooleanQuery lucQuery2 = (Lucene.Net.Search.BooleanQuery)bf.Deserialize(ms);
+#pragma warning restore SYSLIB0011 // Type or member is obsolete (BinaryFormatter)
             ms.Close();
 
             Assert.AreEqual(lucQuery, lucQuery2, "Error in serialization");