Example of the map call (#27)

* added spaish translation

* added the result of a map call, to clarify where is the array, and how the map function works.

* fixed the word components

05-properties.html

@@ -33,6 +33,12 @@ <h2>{props.customData}</h2>
 var planets = ["earth", "mars", "venus"]
 
 // If an array is used as a "child node" each child needs a unique key-property
+// This map call will return an array of components, like this example:
+// [
+// <MyComponent className="myClass" customData={"earth"} key={0}/>,
+// <MyComponent className="myClass" customData={"mars"} key={1}/>,
+// <MyComponent className="myClass" customData={"venus"} key={2}/>
+// ]
 var elements = planets.map(function(planet, index) {
  return <MyComponent className="myClass" customData={planet} key={index}/>
 })