Add some doxygen and rearrange code.

git-svn-id: https://origsvn.digium.com/svn/asterisk/team/mmichelson/threadpool@377209 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/threadpool.h

@@ -93,6 +93,19 @@ struct ast_threadpool *ast_threadpool_create(struct ast_threadpool_listener *lis
  */
 void ast_threadpool_set_size(struct ast_threadpool *threadpool, unsigned int size);
 
+/*!
+ * \brief Push a task to the threadpool
+ *
+ * Tasks pushed into the threadpool will be automatically taken by
+ * one of the threads within
+ * \param pool The threadpool to add the task to
+ * \param task The task to add
+ * \param data The parameter for the task
+ * \retval 0 success
+ * \retval -1 failure
+ */
+int ast_threadpool_push(struct ast_threadpool *pool, int (*task)(void *data), void *data);
+
 /*!
  * \brief Shut down a threadpool and destroy it
  *