Some improvements and new/missing features

[tbe]

Improvements:

• moved to Go Modules
• replaces the custom chef API code with go-chef/chef
• moved testing only code to the unit test

Features:

• implemented role policies
• implemented tag policies
• implemented environment policies
• added support for metadata mapping

[nhuff]

• implemented role policies
• implemented tag policies
• implemented environment policies

I had implemented these originally, but after discussion with some Chef folks it turns out you can't really use these securely because the chef client can change them arbitrarily.

I will take a look at the module conversion and metadata mapping.

[tbe]

I had implemented these originally, but after discussion with some Chef folks it turns out you can't really use these securely because the chef client can change them arbitrarily.

In theory, this is correct. I'm using a lightwight proxy, written in go, in front of the chef server API to disallow changes to the run_list at the moment.

I think there should be a big, fat, warning in the docs about this.

If i find time, i will make the proxy releasable.