Update knife and chef versions

Hey @acidlabs. 
Thanks for good project. 
I need to make some updates to run with newer configuration, this PR contains this changes. 
I have following versions of knife and chef:
```
Chef: 11.8.2
knife-solo (0.4.1)
```
Node runs Ubuntu 12.04. 
You can merge this PR or just take in account changes that are needed for update.

Thanks one more time.