Save http_proxy env variables

[fengb]

This allows a proxy server spun up by hotel to refer to the generated domain names by default.

[typicode]

Sounds good :)
Out of curiosity, what's your OS and the proxy you're using or is it a custom one?

[fengb]

I'm using OS X but I added manual proxy servers into hotel and forgot to update the env variables. I think this default would be helpful for others.

(Of course, node.js core doesn't support http_proxy so that'll cause some confusion... ref: nodejs/node#8381)

[fengb]

Tangentially related: would it make sense to add a hotel env command to spit these out for shell exporting? e.g. eval $(hotel env)

[typicode]

Thank you for the reply. I've not thought about eval $(hotel env) but it's a nice idea. I wonder if there are any limitations to this approach compared to passing HTTP_PROXY env directly.

[typicode]

I've modified the way apps are started so that they all get HTTP_PROXY env, so there's no need to add these variables in each conf.

#142

[fengb]

Neat, thanks!