code: function(node, level, flags) {
          var ans = [], that = this;
          level = level || 0;
          var levelStart, levelEnd;
          if($.type(level) == 'array') {
              levelStart = level[0];
              levelEnd = level[1];
          } else {
              levelStart = level;
              levelEnd = Number.MAX_VALUE - node._depth;
          }
          this.eachLevel(node, levelStart, levelEnd, function(n) {
              ans.push(n);
          }, flags);
          return ans;
      }
docs: /*
  Method: getSubnodes
  
  Collects all subnodes for a specified node.
  The *level* parameter filters nodes having relative depth of *level* from the root node.
  
  Also implemented by:
  
  <Graph.Node>.
  
  Parameters:
  node - (object) A <Graph.Node>.
  level - (optional|number) Default's *0*. A starting relative depth for collecting nodes.
  
  Returns:
  An array of nodes.