Repository reorganisation

Unified kotlin and java into just src/main
Unified the rs09 and core packages
Took all content out of the core package, and placed it into the new content package
Reorganised all source code relating to content to be easier to find and explore

Server/src/main/core/api/Commands.kt

@@ -0,0 +1,49 @@
+package core.api
+
+import core.game.node.entity.player.Player
+import core.game.system.command.Command
+import core.game.system.command.CommandMapping
+import core.game.system.command.Privilege
+import core.tools.colorize
+
+/**
+ * An interface for writing content that allows the class to define commands.
+ *
+ * Includes methods [reject] and [notify] for notifying the player of a command rejection or some output text respectively.
+ *
+ * Includes the method [define] to define individual commands
+ *
+ * Commands should ideally be defined in the required [defineCommands] method.
+ */
+interface Commands : ContentInterface {
+    /**
+     * Glorified player.sendMessage with red text coloring. Please use this
+     * rather than just player.sendMessage for anything that involves informing the player
+     * of proper usage or invalid syntax. Throws an IllegalStateException and ends command execution immediately.
+     */
+    fun reject(player: Player, vararg message: String){
+        for(msg in message) {
+            player.sendMessage(colorize("-->%R$msg"))
+        }
+        throw IllegalStateException()
+    }
+
+    /**
+     * Glorified player.sendMessage with black text coloring and an arrow. Use this when you need to
+     * notify/inform a player of some information from within the command without ending execution.
+     */
+    fun notify(player: Player, message: String){
+        player.sendMessage(colorize("-->$message"))
+    }
+
+    /**
+     * Used to define commands. define("name",(optional) privilege override){ handle }
+     * @param name the name of the command. Example: ::example would be just "example"
+     * @param privilege the rights level needed to execute the command. Options are [Privilege.STANDARD], [Privilege.MODERATOR], [Privilege.ADMIN]. Defaults to [Privilege.STANDARD]
+     */
+    fun define(name: String, privilege: Privilege = Privilege.ADMIN, usage: String = "", description: String = "", handle: (Player, Array<String>) -> Unit){
+        CommandMapping.register(Command(name, privilege, usage, description, handle))
+    }
+
+    fun defineCommands()
+}