move hellofs to examples directory

fuse.go

@@ -39,7 +39,7 @@
 // but few are required.
 // The specific methods are described in the documentation for those interfaces.
 //
-// The hellofs subdirectory contains a simple illustration of the fs.Serve approach.
+// The hellofs example contains a simple illustration of the fs.Serve approach.
 //
 // Service Methods
 //