Moved using inside namespace.

src/ImageSharp/Formats/Jpg/JpegEncoderCore.cs

@@ -3,8 +3,6 @@
 // Licensed under the Apache License, Version 2.0.
 // </copyright>
 
-using System.Numerics;
-
 namespace ImageSharp.Formats
 {
     using System;

src/ImageSharp/Quantizers/Wu/WuQuantizer.cs

@@ -3,12 +3,11 @@
 // Licensed under the Apache License, Version 2.0.
 // </copyright>
 
-using System.Numerics;
-
 namespace ImageSharp.Quantizers
 {
     using System;
     using System.Collections.Generic;
+    using System.Numerics;
     using System.Threading.Tasks;
 
     /// <summary>

src/ImageSharp/Samplers/Processors/RotateProcessor.cs

@@ -3,10 +3,9 @@
 // Licensed under the Apache License, Version 2.0.
 // </copyright>
 
-using System;
-
 namespace ImageSharp.Processors
 {
+    using System;
     using System.Numerics;
     using System.Threading.Tasks;