Fork markan/envy, point to newly-forked chef/envy

[lbakerchef]

We are currently referencing markan/envy and manderson26/envy in:

• chef-server
• sqerl
• mini_s3
• possibly other places.

1. Fork markan/envy to chef/envy.
   This is now done: https://github.com/chef/envy
2. Point chef-server, sqerl, mini_s3, and other applications to chef/envy instead of markan/envy or manderson26/envy.

Related PRs:
chef/sqerl#112

Aha! Link: https://chef.aha.io/features/SH-3058