Fix plugin for Java 8! Add reload command, fix duplication bug, and drop an ES System when the block is broken

The plugin was majorly broken on Java 8 but now its fixed! I also added a reload command: /esreload with an accompanying permission: energeticstorage.reload. This also fixes an other duplication bug when the user would right click a stack of items into the terminal. More info about the bug here. I also made it so when an ES System is broken, it will drop a head named ES System instead of a Player Head.