Unix Timestamp helper

Octokit/Helpers/UnixTimeStampExtensions.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace Octokit.Helpers
+{
+    public static class UnixTimestampExtensions
+    {
+        const long _unixEpochTicks = 621355968000000000; // Unix Epoch is January 1, 1970 00:00 -0:00
+        
+        public static DateTimeOffset FromUnixTime(this long unixTime)
+        {
+            return new DateTimeOffset(unixTime * TimeSpan.TicksPerSecond + _unixEpochTicks, TimeSpan.Zero);
+        }
+    }
+}