loadServices(folder = "./services", fileMask = "**/*.service.js") {
		this.logger.debug(`Search services in '${folder}/${fileMask}'...`);

		let serviceFiles;

		if (Array.isArray(fileMask)) serviceFiles = fileMask.map(f => path.join(folder, f));
		else serviceFiles = glob.sync(path.join(folder, fileMask));

		if (serviceFiles) serviceFiles.forEach(filename => this.loadService(filename));

		return serviceFiles.length;
	}
Load services from a folder

@param {string} [folder="./services"]		Folder of services
@param {string} [fileMask="**\/*.service.js"]	Service filename mask
@returns	{Number}							Number of found services

@memberof ServiceBroker