code: function Tree(options) {
  		this.root = new Node(this, options);
  		this.unique = options && options.unique || false;
  		this.compare = options && options.compare || compare;
  		this.equals = options && options.equals || equals;
  		this.keyType = options && options.keyType || undefined;
  		this.id = options && options.id || undefined;
  	}
docs: Creates a new Tree.
  
  @param {Object} Optional options object
  @param {Boolean}  options.unique Whether to enforce a 'unique' constraint on the key or not
  @param {Function} options.compare Optional key comparison function
  @param {Function} options.equals Optional data equality comparison function
  @param {Function} options.keyType Optional constructor function for when key type is not primitive
  @param {Function} options.id Optional id extraction function