Improved the Scheduler.

Adds nag message when async tasks are not properly shut down and adds a limiter for sync tasks. Once they use 35ms in a single tick, any remaining tasks are not executed until later ticks. Adds a method to report the pending tasks and one to report active worker threads

src/main/java/org/bukkit/scheduler/BukkitWorker.java

@@ -0,0 +1,35 @@
+package org.bukkit.scheduler;
+
+import org.bukkit.plugin.Plugin;
+
+/**
+ * Represents a worker thread for the scheduler.  This gives information about
+ * the Thread object for the task, owner of the task and the taskId.
+ *
+ * Workers are used to execute async tasks.
+ */
+
+public interface BukkitWorker {
+
+    /**
+     * Returns the taskId for the task being executed by this worker
+     *
+     * @return Task id number
+     */
+    public int getTaskId();
+
+    /**
+     * Returns the Plugin that owns this task
+     *
+     * @return The Plugin that owns the task
+     */
+    public Plugin getOwner();
+
+    /**
+     * Returns the thread for the worker
+     *
+     * @return The Thread object for the worker
+     */
+    public Thread getThread();
+
+}