fix(templates:common): Lint bower.json before executing wiredep.

[Yatoom]

I recommend linting bower.json before running wiredep. When there is, say, a trailling comma in bower.json and the wiredep task (grunt wiredep) is executed, the user will not get a very helpful message:

Running "wiredep:app" (wiredep) task
Warning: Unexpected token } Use --force to continue.

Aborted due to warnings.

You see, the error could be in any file. By running jsonlint first, we get a much more helpful error message.

Running "jsonlint:all" (jsonlint) task
>> File "bower.json" failed JSON validation.
Warning: Parse error on line 15:
...nario": "~1.3.6",  },  "resolutions": 
----------------------^
Expecting 'STRING', got '}' Use --force to continue.

Aborted due to warnings.

If everything is fine, the user will see the following messages:

Running "jsonlint:all" (jsonlint) task
>> 1 file lint free.

Running "wiredep:app" (wiredep) task