Update pom.xml to use aven-assembly-plugin instead.

pom.xml

@@ -12,21 +12,25 @@
             <url>https://m2.dv8tion.net/releases</url>
         </repository>
     </repositories>
-    <build>
+        <build>
-		<plugins>
+            <plugins>
-			<plugin>
+                <plugin>
-				<groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-assembly-plugin</artifactId>
-				<artifactId>maven-jar-plugin</artifactId>
+                    <configuration>
-				<configuration>
+                        <archive>
-					<archive>
+                            <manifest>
-						<manifest>
+                                <mainClass>
-							<mainClass>moe.nekojimi.chords.Main</mainClass>
+                                    moe.nekojimi.chords.Main
-						</manifest>
+                                </mainClass>
-					</archive>
+                            </manifest>
-				</configuration>
+                        </archive>
-			</plugin>
+                        <descriptorRefs>
-		</plugins>
+                            <descriptorRef>jar-with-dependencies</descriptorRef>
-    </build>
+                        </descriptorRefs>
+                    </configuration>
+                </plugin>
+            </plugins>
+        </build>
     <dependencies>
         <dependency>
             <groupId>net.dv8tion</groupId>