Optimize travis build with publish option

.travis.yml

@@ -6,7 +6,7 @@ before_install:
   - npm install -g grunt-cli
 
 script:
-  - grunt --stack default sauce metrics publish:latest
+  - grunt --stack travis
 
 email:
   on_failure: change
@@ -21,6 +21,7 @@ matrix:
   include:
     - node_js: "0.10"
       env:
+        - PUBLISH=true
         - secure: pLTzghtVll9yGKJI0AaB0uI8GypfWxLTaIB0ZL8//yN3nAEIKMhf/RRilYTsn/rKj2NUa7vt2edYILi3lttOUlCBOwTc9amiRms1W8Lwr/3IdWPeBLvLuH1zNJRm2lBAwU4LBSqaOwhGaxOQr6KHTnWudhNhgOucxpZfvfI/dFw=
         - secure: yERYCf7AwL11D9uMtacly/THGV8BlzsMmrt+iQVvGA3GaY6QMmfYqf6P6cCH98sH5etd1Y+1e6YrPeMjqI6lyRllT7FptoyOdHulazQe86VQN4sc0EpqMlH088kB7gGjTut9Z+X9ViooT5XEh9WA5jXEI9pXhQJNoIHkWPuwGuY=
 

Gruntfile.js

@@ -184,5 +184,7 @@ module.exports = function(grunt) {
   grunt.registerTask('bench', ['metrics']);
   grunt.registerTask('sauce', process.env.SAUCE_USERNAME ? ['tests', 'connect', 'saucelabs-mocha'] : []);
 
+  grunt.registerTask('travis', process.env.PUBLISH ? ['default', 'sauce', 'metrics', 'publish:latest'] : ['default']);
+
   grunt.registerTask('default', ['build', 'test', 'release']);
 };