Add FromUnixTimestamp function

Ref #2

tUtils/Utils.cs

@@ -18,6 +18,17 @@ namespace tUtils
             return (long)span.TotalMilliseconds;
         }
 
+        /// <summary>
+        /// Convert unix timestamp in millis to datetime.
+        /// </summary>
+        /// <param name="timestamp"></param>
+        /// <returns>Datetime</returns>
+        public static DateTime FromUnixTimestamp(this long timestamp)
+        {
+            DateTime dtDateTime = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
+            dtDateTime = dtDateTime.AddMilliseconds(timestamp);
+            return dtDateTime;
+        }
         /// <summary>
         /// 
         /// </summary>