Add bower install before grunt to fix bug build error, because of missin...

...g bower sizzle

```
Running "build:all:*" (build) task
Warning: Error: ENOENT, no such file or directory '/var/jquery/src/../bower_components/sizzle/dist/sizzle.js'
In module tree:
    jquery
      selector
        selector-sizzle

    at Object.fs.openSync (fs.js:338:18)
 Use --force to continue.
```
Aborted due to warnings.