_content/tour: fix content test
- Add missing '// +build' comments for generics examples.
- Add build tags 'OMIT', 'no-run' for solutions examples.
- Move content_test.go to the root because 'go' ignores
packages in the '_content' directory.
- Remove usages of deprecated 'io/ioutil'.
Change-Id: I8e6b717d43df9e2b55e4b796db5b316860f42103
Reviewed-on: https://go-review.googlesource.com/c/website/+/592875
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
diff --git a/_content/tour/solutions/rot13.go b/_content/tour/solutions/rot13.go
index 84315a4..8edce64 100644
--- a/_content/tour/solutions/rot13.go
+++ b/_content/tour/solutions/rot13.go
@@ -1,9 +1,9 @@
+// +build OMIT ignore
+
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
-// +build ignore
-
package main
import (
