Adds an error message when people list is not accessible

When the frontend tries to recover people list and the request fails a
message is shown to notify the user.

pom.xml

@@ -5,7 +5,7 @@
 	<groupId>es.uvigo.esei.daa</groupId>
 	<artifactId>example</artifactId>
 	<packaging>war</packaging>
-	<version>0.1.11</version>
+	<version>0.1.12</version>
 	<name>DAA Example</name>
 
 	<licenses>

src/main/webapp/js/view/people.js

@@ -21,6 +21,9 @@ var PeopleView = (function() {
 				$.each(people, function(key, person) {
 					appendToTable(person);
 				});
+			},
+			function() {
+			    	alert('No has sido posible acceder al listado de personas.');
 			});
 			
 			// La acción por defecto de enviar formulario (submit) se sobreescribe