Switch to latest grunt-contrib-copy for less blabla
Update grunt-contrib-watch to fix reloading "Unable to find Gruntfile" message

```
Reloading watch config...
A valid Gruntfile could not be found. Please see the getting started
guide for
more information on how to configure grunt:
http://gruntjs.com/getting-started
Fatal error: Unable to find Gruntfile.
```