[MAJOR] replace ultree with ebtree in wait-queues

The ultree code has been removed in favor of a simpler and
cleaner ebtree implementation. The eternity queue does not
need to exist anymore, and the pool_tree64 has been removed.

The ebtree node is stored in the task itself. The qlist list
header is still used by the run-queue, but will be able to
disappear once the run-queue uses ebtree too.
diff --git a/src/proto_uxst.c b/src/proto_uxst.c
index b708689..c4c3d37 100644
--- a/src/proto_uxst.c
+++ b/src/proto_uxst.c
@@ -444,9 +444,7 @@
 			return 0;
 		}
 
-		t->wq = NULL;
-		t->qlist.p = NULL;
-		t->state = TASK_IDLE;
+		task_init(t);
 		t->process = l->handler;
 		t->context = s;
 
@@ -527,7 +525,6 @@
 			t->expire = s->req->rex;
 		}
 
-		task_queue(t);
 		task_wakeup(t);
 
 		l->nbconn++; /* warning! right now, it's up to the handler to decrease this */