Split up the samples package.

samples/hello_fs.go → samples/hellofs/hello_fs.go

 // Copyright 2015 Google Inc. All Rights Reserved.
 // Author: jacobsa@google.com (Aaron Jacobs)
 
-package samples
+package hellofs
 
 import (
 	"io"

samples/hello_fs_test.go → samples/hellofs/hello_fs_test.go

 // Copyright 2015 Google Inc. All Rights Reserved.
 // Author: jacobsa@google.com (Aaron Jacobs)
 
-package samples_test
+package hellofs_test
 
 import (
 	"io"

samples/mem_fs.go → samples/memfs/mem_fs.go

 // Copyright 2015 Google Inc. All Rights Reserved.
 // Author: jacobsa@google.com (Aaron Jacobs)
 
-package samples
+package memfs
 
 import (
 	"sync"