I'm trying to install various plug-ins(Black button, Essentials, ChestLock, and GingerSnap). I download them and put them into the plugins folder on my Macbook Air late-2013 11". I double-click start_server.command and the server starts. But it shows no sign of plugins installing. It just runs, without any plugins at all. This is basically what it looks like. Please help! Most of the information needed is in the snapshot.