Release task now always publishes to staging

Production builds should never be published directly from a local
machine. Instead, the release command will now publish to a
commit-specific staging URL, so you use it to publish a release
candidate, and then when those builds have been verified, you need to
copy the RC builds from on the staging location on s3 to the production
folder.

package.json

@@ -48,6 +48,7 @@
     "test:server": "grunt test:server",
     "test:coverage": "grunt test:coverage",
     "build": "grunt build",
+    "release": "grunt release",
     "start": "sh ./bin/kibana --dev",
     "precommit": "grunt precommit",
     "karma": "karma start",

tasks/release.js

@@ -38,6 +38,8 @@ module.exports = function (grunt) {
   });
 
   grunt.registerTask('_release:setS3Uploads', function () {
+    const { sha, version } = grunt.config.get('build');
+
     var uploads = grunt.config.get('platforms')
     .reduce(function (files, platform) {
       return files.concat(
@@ -61,10 +63,12 @@ module.exports = function (grunt) {
       }
     })
     .map(function (filename) {
-      return {
-        src: 'target/' + filename,
-        dest: 'kibana/kibana/' + filename
-      };
+      const src = `target/${filename}`;
+
+      const shortSha = sha.substr(0, 7);
+      const dest = `kibana/staging/${version}-${shortSha}/kibana/${filename}`;
+
+      return { src, dest };
     });
     grunt.config.set('s3.release.upload', uploads);
   });