DAS HIER IST DIE ERROR MESSAGE:
[15:40:30 ERROR]: Could not load 'plugins/BedwarsRel.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: io/github/yannici/bedwars/Main : Unsupported major.minor version 51.0
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:133) ~[bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:328) ~[bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugins(CraftServer.java:289) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.reload(CraftServer.java:718) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.Bukkit.reload(Bukkit.java:544) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:25) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:140) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchCommand(CraftServer.java:620) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchServerCommand(CraftServer.java:606) [bukkit.jar:git-Bukkit-18fbb24]
	at net.minecraft.server.v1_8_R3.DedicatedServer.aO(DedicatedServer.java:372) [bukkit.jar:git-Bukkit-18fbb24]
	at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:336) [bukkit.jar:git-Bukkit-18fbb24]
	at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:629) [bukkit.jar:git-Bukkit-18fbb24]
	at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:537) [bukkit.jar:git-Bukkit-18fbb24]
	at java.lang.Thread.run(Thread.java:695) [?:1.6.0_65]
Caused by: java.lang.UnsupportedClassVersionError: io/github/yannici/bedwars/Main : Unsupported major.minor version 51.0
	at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.6.0_65]
	at java.lang.ClassLoader.defineClassCond(ClassLoader.java:637) ~[?:1.6.0_65]
	at java.lang.ClassLoader.defineClass(ClassLoader.java:621) ~[?:1.6.0_65]
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) ~[?:1.6.0_65]
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:283) ~[?:1.6.0_65]
	at java.net.URLClassLoader.access$000(URLClassLoader.java:58) ~[?:1.6.0_65]
	at java.net.URLClassLoader$1.run(URLClassLoader.java:197) ~[?:1.6.0_65]
	at java.security.AccessController.doPrivileged(Native Method) ~[?:1.6.0_65]
	at java.net.URLClassLoader.findClass(URLClassLoader.java:190) ~[?:1.6.0_65]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:77) ~[bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:62) ~[bukkit.jar:git-Bukkit-18fbb24]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:306) ~[?:1.6.0_65]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:247) ~[?:1.6.0_65]
	at java.lang.Class.forName0(Native Method) ~[?:1.6.0_65]
	at java.lang.Class.forName(Class.java:249) ~[?:1.6.0_65]
	at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:40) ~[bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:129) ~[bukkit.jar:git-Bukkit-18fbb24]
	... 14 more
[
java.lang.ClassCastException: java.util.jar.JarFile cannot be cast to java.io.Closeable
	at com.sk89q.worldedit.util.io.Closer.close(Closer.java:153) ~[?:?]
	at com.sk89q.worldedit.bukkit.adapter.BukkitImplLoader.addFromJar(BukkitImplLoader.java:104) ~[?:?]
	at com.sk89q.worldedit.bukkit.WorldEditPlugin.loadAdapter(WorldEditPlugin.java:142) ~[?:?]
	at com.sk89q.worldedit.bukkit.WorldEditPlugin.onEnable(WorldEditPlugin.java:119) ~[?:?]
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321) ~[bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:332) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:404) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugin(CraftServer.java:342) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.enablePlugins(CraftServer.java:314) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.reload(CraftServer.java:720) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.Bukkit.reload(Bukkit.java:544) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:25) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:140) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchCommand(CraftServer.java:620) [bukkit.jar:git-Bukkit-18fbb24]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchServerCommand(CraftServer.java:606) [bukkit.jar:git-Bukkit-18fbb24]
	at net.minecraft.server.v1_8_R3.DedicatedServer.aO(DedicatedServer.java:372) [bukkit.jar:git-Bukkit-18fbb24]
	at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:336) [bukkit.jar:git-Bukkit-18fbb24]
	at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:629) [bukkit.jar:git-Bukkit-18fbb24]
	at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:537) [bukkit.jar:git-Bukkit-18fbb24]
	at java.lang.Thread.run(Thread.java:695) [?:1.6.0_65]