Emit the input focus event (olefirenko#9)

* Emit the input focus event

* Complete the doc

Author: julianfox

README.md

@@ -63,6 +63,7 @@ In your template you can use this syntax:
     classname="form-control"
     placeholder="Start typing"
     v-on:placechanged="getFromData"
+    v-on:focus="onFocus"
 >
 </vue-google-autocomplete>
 ```

src/VueGoogleAutocomplete.vue

@@ -3,7 +3,7 @@
         :class="classname"
         :id="id"
         :placeholder="placeholder"
-        @focus = "geolocate()"
+        @focus = "onFocus()"
     />
 </template>
 
@@ -104,6 +104,10 @@
         },
 
         methods: {
+            onFocus() {
+              this.geolocate()
+              this.$emit('focus')
+            },
             // Bias the autocomplete object to the user's geographical location,
             // as supplied by the browser's 'navigator.geolocation' object.
             geolocate() {