fix include context

Author: aisk

lib/av.js

@@ -16,7 +16,12 @@ var fs = require('fs');
 var vm = require('vm');
 var path = require('path');
 
-var context = vm.createContext();
+var context = vm.createContext({
+  console: console,
+  exports: exports,
+  module: module,
+  require: require,
+});
 
 var include = function(filename) {
   var script = fs.readFileSync(path.join(__dirname, filename), {'encoding': 'utf-8'});