Minor cleanup.

* Replaced a stray int with var.
    * Reordered some using directives.
    * Removed some unused using directives.

DotSDL/Events/EventHandler.cs

@@ -47,8 +47,7 @@ namespace DotSDL.Events {
 
             while(SdlEvents.PollEvent(ref inEvent) != 0) {
                 var newEvent = ConvertEvent(inEvent);
-                if(newEvent is null) continue;
-                if(newEvent.Resource != null)
+                if(newEvent?.Resource != null)
                     EventDispatcher.Dispatch(newEvent);
             }
         }

DotSDL/Graphics/Canvas.cs

@@ -1,6 +1,4 @@
-using System;
-
-namespace DotSDL.Graphics {
+namespace DotSDL.Graphics {
     /// <summary>
     /// A representation of the contents of the SDL window, with a number of
     /// helper routines.

DotSDL/Graphics/SdlWindow.cs

@@ -1,7 +1,7 @@
 using DotSDL.Events;
+using DotSDL.Input;
 using DotSDL.Sdl;
 using System;
-using DotSDL.Input;
 
 namespace DotSDL.Graphics {
     /// <summary>

Samples/Sample.Audio/Window.cs

@@ -80,7 +80,7 @@ namespace Sample.Audio {
             // Number
             var freqText = _freq.ToString();
             var textPos = 5 - freqText.Length;
-            for(int x = 0; x < freqText.Length; x++)
+            for(var x = 0; x < freqText.Length; x++)
                 DrawGlyph(ref canvas, freqText[x], textPos + x, _textColor);
 
             // Background/highlighting.