improve reset impl

src/by/By.Reset.cs

@@ -1,11 +1,36 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
 namespace Byter
 {
     public partial class By : IBy
     {
         public void Reset()
+        {
+            InternalReset(Array.Empty<byte>());
+        }
+
+        public void Reset(byte[] buffer)
+        {
+            InternalReset((buffer == null || buffer.Length <= 0) ? Array.Empty<byte>() : buffer.ToArray());
+        }
+
+        public void Reset(List<byte> buffer)
+        {
+            InternalReset((buffer == null || buffer.Count <= 0) ? Array.Empty<byte>() : buffer.ToArray());
+        }
+
+        private void InternalReset(byte[] buffer)
         {
             Index = 0;
             IsValid = true;
+            _vault.Clear();
+
+            if (buffer != null && buffer.Length >= 1)
+            {
+                _vault.AddRange(buffer);
+            }
         }
     }
 }

src/by/IBy.cs

@@ -1,3 +1,5 @@
+using System.Collections.Generic;
+
 namespace Byter
 {
     internal interface IBy
@@ -7,6 +9,8 @@ internal interface IBy
         byte[] Buffer { get; }
 
         void Reset();
+        void Reset(byte[] buffer);
+        void Reset(List<byte> buffer);
         void Add<T>(T value);
         T Get<T>();
     }