Make sure release notes and artifacts file uploaded to appveyor

Author: JakeGinnivan

build.cake

@@ -162,6 +162,8 @@ Task("Upload-AppVeyor-Artifacts")
     AppVeyor.UploadArtifact("build/GitVersionTfsTaskBuild/gittools.gitversion-" + semVersion + ".vsix");
     AppVeyor.UploadArtifact("build/GitVersion_" + nugetVersion + ".zip");
     AppVeyor.UploadArtifact("build/GemBuild/" + gem);
+    AppVeyor.UploadArtifact("releasenotes.md");
+    AppVeyor.UploadArtifact("build/artifacts");
 });