fixes

Author: Alex Peck

BitFaster.Caching.Benchmarks/Lfu/CmSketchFlat.cs

@@ -199,7 +199,7 @@ private int IndexOf(int item, int i)
             return ((int)hash) & tableMask;
         }
 
-        private int Spread(int x)
+        private static int Spread(int x)
         {
             uint y = (uint)x;
             y = ((y >> 16) ^ y) * 0x45d9f3b;

BitFaster.Caching/Atomic/AtomicEx.cs

@@ -3,7 +3,6 @@
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Linq;
-using System.Text;
 
 namespace BitFaster.Caching.Atomic
 {
@@ -21,6 +20,7 @@ internal static int EnumerateCount(IEnumerator enumerator)
 
         internal static ICollection<K> FilterKeys<K, V>(IEnumerable<KeyValuePair<K, V>> kvps, Func<V, bool> filter)
         {
+#pragma warning disable CA1851
             // Here we will double enumerate the kvps list. Alternative is to lazy init the size which will keep resizing
             // the List, and spam allocs if the list is long.
             List<K> keys = new List<K>(kvps.Count());
@@ -34,6 +34,7 @@ internal static ICollection<K> FilterKeys<K, V>(IEnumerable<KeyValuePair<K, V>>
             }
 
             return new ReadOnlyCollection<K>(keys);
+#pragma warning restore CA1851
         }
     }
 }