Update Maven shade plugin used in project generation to 2.4

Author: DenWav

src/main/resources/fileTemplates/j2ee/bukkit_pom_template.xml.ft

@@ -30,7 +30,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-shade-plugin</artifactId>
-        <version>2.3</version>
+        <version>2.4</version>
         <executions>
           <execution>
             <phase>package</phase>

src/main/resources/fileTemplates/j2ee/bungeecord_pom_template.xml.ft

@@ -30,7 +30,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-shade-plugin</artifactId>
-        <version>2.3</version>
+        <version>2.4</version>
         <executions>
           <execution>
             <phase>package</phase>

src/main/resources/fileTemplates/j2ee/canary_pom_template.xml.ft

@@ -30,7 +30,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-shade-plugin</artifactId>
-        <version>2.3</version>
+        <version>2.4</version>
         <executions>
           <execution>
             <phase>package</phase>