Add vendor

vendor/github.com/kr/fs/example_test.go

@@ -0,0 +1,19 @@
+package fs_test
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/kr/fs"
+)
+
+func ExampleWalker() {
+	walker := fs.Walk("/usr/lib")
+	for walker.Step() {
+		if err := walker.Err(); err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			continue
+		}
+		fmt.Println(walker.Path())
+	}
+}