Top level config name is inappropriately cached in ENV

[iwarshak]

Given the examples, specifically the API_ENV configuration...

Running in the sim with: rake API_ENV=development the first time is fine, and if you inspect ENV['API_ENV'], you get 'development', as expected

However, if you run it again with API_ENV=staging, then in the code inspecting ENV['API_ENV'] will be development NOT staging.

RMENV['API_ENV'] has the correct result and ENV["HOST"] has the correct result

So it seems that the hash values for the top level gets cached somewhere. Hopefully this makes sense.