code: function _createTasks(tree, parent, tasks) {
  	parent = parent || "";
  	tasks = tasks || {};
  
  	for (var id in tree) {
  		if (tree[id].deps && tree[id].fn) {
  			tasks[parentId(parent, id)] = tree[id];
  		} else {
  			_createTasks(tree[id], parentId(parent, id) + ':', tasks)
  		}
  	}
  
  	return tasks;
  }
docs: Given a tree structure, create an object of tasks-ids against task objects.
  
  @param {Object} tree				The directory tree from tree().
  @param {string} [parent=""]		The current parent id.
  @param {Object} [tasks={}]		The task object.
  @returns {Object}				The flat object, tasks.