Better handling when 'default' task is missing from gulpfile.js

### Changing this:
![Original](http://than.pol.as/Sxtl/Screen%20Shot%202013-12-16%20at%209.07.19%20PM.png)

### To this:
![Changed to](http://than.pol.as/Syqj/Screen%20Shot%202013-12-16%20at%209.06.34%20PM.png)

When there is no `default` task defined in the `gulpfile.js` file.