[07:08:31] [Server thread/ERROR]: Could not load 'plugins/CORE-0.1-SNAPSHOT.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.NoClassDefFoundError: net/minecraft/util/com/google/gson/Gson
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:133) ~[lspigot.jar:git-PaperSpigot-"4c7641d"]
	at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:331) ~[lspigot.jar:git-PaperSpigot-"4c7641d"]
	at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:254) [lspigot.jar:git-PaperSpigot-"4c7641d"]
	at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugins(CraftServer.java:293) [lspigot.jar:git-PaperSpigot-"4c7641d"]
	at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:202) [lspigot.jar:git-PaperSpigot-"4c7641d"]
	at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:563) [lspigot.jar:git-PaperSpigot-"4c7641d"]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_191]
Caused by: java.lang.NoClassDefFoundError: net/minecraft/util/com/google/gson/Gson
	at pl.sentria.core.Main.<clinit>(Main.java:54) ~[?:?]
	at java.lang.Class.forName0(Native Method) ~[?:1.8.0_191]
	at java.lang.Class.forName(Class.java:348) ~[?:1.8.0_191]
	at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:65) ~[lspigot.jar:git-PaperSpigot-"4c7641d"]
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:129) ~[lspigot.jar:git-PaperSpigot-"4c7641d"]
	... 6 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.util.com.google.gson.Gson
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:92) ~[lspigot.jar:git-PaperSpigot-"4c7641d"]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:87) ~[lspigot.jar:git-PaperSpigot-"4c7641d"]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_191]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_191]
	at pl.sentria.core.Main.<clinit>(Main.java:54) ~[?:?]
	at java.lang.Class.forName0(Native Method) ~[?:1.8.0_191]
	at java.lang.Class.forName(Class.java:348) ~[?:1.8.0_191]
	at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:65) ~[lspigot.jar:git-PaperSpigot-"4c7641d"]
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:129) ~[lspigot.jar:git-PaperSpigot-"4c7641d"]
	... 6 more