Fix travis build

 - Add SinonJS via require
 - Use HTTPS for timepicker dependency

Yeah, doesn't seem happy with the ssh url format ```git://github.com:<username>...``` unless we give it access via ssh keys. Looks like we can/should use the public url format instead i.e. 
```
git@github.com/BrandwatchLtd/timepicker.git
```
Will give that a go.