Questions left unanswered

Throughout the show we've been shown various things that leave me asking questions. But right now I'm wondering about the Golden Oaks Library. In "Too Many Pinkie Pies", back before Tirek blew it up, Spike found a secret compartment. Who put the compartment there, and why did they put the book there? My guess would be Golden Oaks himself. Think about it: why else would the Ponyville town library be named that unless it was named after the pony that lived there? I'm really looking forward to Season 5. Hopefully they'll explain it then.