utils.js
function listAvailables(forceRefresh) {
	forceRefresh && (adaptersCache = []);

	if( adaptersCache.length ){
		return adaptersCache;
	}

	adaptersCache = fs.readdirSync(__dirname).filter(function(fileOrDirName){
		return isDir(__dirname + '/' + fileOrDirName);
	});
	return adaptersCache;
}
function listAvailables(forceRefresh) {
	forceRefresh && (adaptersCache = []);

	if( adaptersCache.length ){
		return adaptersCache;
	}

	adaptersCache = fs.readdirSync(__dirname).filter(function(fileOrDirName){
		return isDir(__dirname + '/' + fileOrDirName);
	});
	return adaptersCache;
}
return a cached list of availables adapter unless forceRefresh is true
@param {boolean} forceRefresh force to refresh the cache of availables adapter