Scheduler

It's a half done pull request, need some feedback to improvement the code. It's aim to schedule the user configured task resource requests.
Mainly done: 
1. move the package into cluster
2. package workerInfo( Todo: using host:port)
3. parse the configuration into task arrangement


private def assign(pendingRequest) = {
  val workerId = pendingRequest.workerId
  if (null != workerId) {
    val availableResource = resoruces(workerId)
   if (avaialbeResource > pendingRequest.requestedResuce) { 
     assignResourceToApplication(allocated.add(request.resource))
  } else {
     ...   
  }
 }
}