Modularizes the Maven project

This commit modularizes the maven project into several modules:
 - l2jserver2-common: common sources for both login and gameserver
 - l2jserver2-gameserver: the game server
 - l2jserver2-loginserver: the login server
 - l2jserver2-tools: refactored src/tools/java soure folder

l2jserver2-gameserver/data/plugin/com/l2jserver/plugin/DisabledPlugin.java

@@ -0,0 +1,19 @@
+package com.l2jserver.plugin;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Marker annotation that is used to mark disabled plugins so they will be
+ * ignored by {@link PluginLoader}
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+public @interface DisabledPlugin {
+}