function Importador(){}
Importador.prototype = {
		import : function(files){
			return Promise.all(files.map(function(file){
				var type = file['type'];
				var url = file['url'];
				var tag = document.createElement(type);
				switch(type){
				case 'script':
					tag.src = url;
					break;
				case 'link':
					tab.href = url;
					break;
				};
				if (!document.querySelector('['+type+'*="'+url+']"')) {					
					return new Promise(function(resolve,reject){					
						tag.onload = function(){
							resolve();
						};
						tag.onerror = function(){
							reject();
						}
						document.body.appendChild(tag);
					});
				} else {
					return Promise.resolve();
				}
			}));
		}
}