code: function _addPlugin(context, name, module, user_plugin) {
  	if (_.isString(module))
  		module = require(module)
  	
  	if (user_plugin && !module.active || module.active === false)
  		// exit if a user_plugin isn't explicitly made active
  		// exit if an inbuilt plugin is explicitly made inactive (never happens, probably)
  		return null;
  
  	var plugin;
  
  	if (module.render && _.isFunction(module.render)) {
  		if (user_plugin)
  			l.vlog("Loading renderer: '" + name + "'");
  		plugin = context._renderers.add(name, module, user_plugin);
  	}
  	else {
  		if (user_plugin)
  			l.vlog("Loading plugin: '" + name + "'");
  		plugin = context._plugins.add(name, module, user_plugin);
  	}
  	return plugin;
  }
docs: /*
  API functions