Update the generator to add translation capability

src/generators/app/templates/TRANSLATION.md

@@ -0,0 +1,22 @@
+A Kibana translation plugin structure. 
+
+The main goal is to keep the plugin extremely simple so non-technical translators will have no trouble
+creating new translations for Kibana. Everything except for the translations themselves can be generated
+automatically with some enhancements to the Kibana plugin generator. The generator would only need a
+plugin name and a list of one or more languages the user wants to create translations for.
+
+The plugin exports its translation file(s) on the server when it it starts up. This is achieved by publishing the files 
+via 'uiExports'.This is configurable by modifying the 'translations' item in the 'uiExports'.
+
+Translation files are broken up by language and must have names that match IETF BCP 47 language codes.
+Each translation file contains a single flat object with translation strings matched to their unique keys. Keys are
+prefixed with plugin names and a dash to ensure uniqueness between plugins. A translation plugin is not restricted to 
+providing translations only for itself, the provided translations can cover other plugins as well.
+
+For example, this template plugin shows how a third party plugin might provide spanish translations for the Kibana core "kibana" app, which is itself a separate plugin.
+
+To create a translation plugin using this template, follow these steps:
+  1. Generate the plugin using the generator
+  2. Add your translations files to <plugin_name>/translations directory. Remove/Overwrite the existing translation file (i.e. 'es.json').
+  3. Edit <plugin_name>/index.js, updating the 'translations' item as per your plugin translations.
+  4. Restart the Kibana server to publish your plugin translations.

src/generators/app/templates/index.js

@@ -1,3 +1,4 @@
+<% if (generateApp) { %>import { resolve } from 'path';<% } %>
 <% if (generateApi) { %>import exampleRoute from './server/routes/example';<% } %>
 
 export default function (kibana) {
@@ -11,6 +12,9 @@ export default function (kibana) {
         description: '<%= description %>',
         main: 'plugins/<%= name %>/app'
       },
+      translations: [
+        resolve(__dirname, './translations/es.json')
+      ],
       <% } %>
       <% if (generateHack) { %>
       hacks: [

src/generators/app/templates/translations/es.json

@@ -0,0 +1,4 @@
+{
+  "UI-WELCOME_MESSAGE": "Cargando Kibana",
+  "UI-WELCOME_ERROR": "Kibana no se cargó correctamente. Heck la salida del servidor para obtener más información."
+}