merge two Tasked methods

In practice, the returned task is coupled to the conversion function,
so task and taskToNode were merged.  Also, renamed 'task' to 'act'.

main/Command.scala

@@ -86,8 +86,7 @@ trait Member[Node <: Member[Node]]
 trait Tasked
 {
 	type Task[T] <: AnyRef
-	def task(name: String, state: State): Option[Task[State]]
-	implicit def taskToNode: NodeView[Task]
+	def act(in: Input, state: State): Option[(Task[State], NodeView[Task])]
 	def help: Seq[Help]
 }
 trait TaskSetup

main/Main.scala

@@ -200,8 +200,8 @@ object Commands
 					case c: TaskSetup => (c.checkCycles, c.maxThreads)
 					case _ => (false, Runtime.getRuntime.availableProcessors)
 				}
-				for(task <- p.task(in.name, s)) yield
-					processResult(runTask(task, checkCycles, maxThreads)(p.taskToNode), s)
+				for( (task, taskToNode) <- p.act(in, s)) yield
+					processResult(runTask(task, checkCycles, maxThreads)(taskToNode), s)
 			}
 		}
 	}