Added Threading package docs

Author: jamesmcroft

docs/articles/features/threading.md

@@ -5,3 +5,81 @@ title: Using the Threading package | MADE.NET
 
 # Using the Threading package
 
+## Modernizing System.Threading.Timer with the MADE.Threading.Timer
+
+Setting up and managing a `System.Threading.Timer` can sometimes be cumbersome. How do you control the start and stop state? 
+
+The `MADE.Threading.Timer` is a modern take on `System.Threading.Timer` providing properties for configuring the `Interval` and `DueTime`, plus an event handler for `Tick`. 
+
+It also includes simple methods to `Start` and `Stop` the timer running.
+
+Below is an example of using the `MADE.Threading.Timer` to setup and start running a timed job.
+
+```csharp
+public class TimerJob
+{
+    private MADE.Threading.Timer processTimer;
+
+    public TimerJob()
+    {
+        processTimer = new MADE.Threading.Timer { Interval = TimeSpan.FromMinutes(1) };
+        processTimer.Tick += OnProcessTimerTick;
+    }
+
+    public void StartTimer()
+    {
+        processTimer.Start();
+    }
+
+    public void StopTimer()
+    {
+        processTimer.Stop();
+    }
+
+
+    private void OnProcessTimerTick(object sender, object e)
+    {
+        // Do work.
+    }
+}
+```
+
+The equivalent for the `System.Threading.Timer` would look like
+
+```csharp
+public class TimerJob
+{
+    private System.Threading.Timer processTimer;
+
+    public void StartTimer()
+    {
+        if (processTimer == null)
+        {
+            processTimer = new System.Threading.Timer(
+                c => this.OnProcessTimerTick(),
+                null,
+                0,
+                (int)Math.Ceiling(TimeSpan.FromMinutes(1).TotalMilliseconds));
+        }
+        else
+        {
+            processTimer.Change(
+               0,
+               (int)Math.Ceiling(TimeSpan.FromMinutes(1).TotalMilliseconds));
+        }
+    }
+
+    public void StopTimer()
+    {
+        processTimer?.Change(Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
+    }
+
+
+    private void OnProcessTimerTick()
+    {
+        // Do work.
+    }
+}
+```
+
+As you can see, the MADE implementation performs the same actions, but is much more concise and a lot easier to understand.