HTTP(s) Proxy support

[cp-whatcha]

Receiving the error
netbootxyz | There was a problem with the fetch operation: request to https://api.github.com/repos/netbootxyz/netboot.xyz/releases/latest failed, reason: connect ETIMEDOUT 140.82.113.5:443

It seems that node.js is not utilizing the proxy environment variables that I am sending the system.

I have attempted to use
http_proxy=http://proxyip:3128
https_proxy=http://proxyip:3128
HTTP_PROXY=http://proxyip:3128
HTTPS_PROXY=http://proxyip:3128
proxyHost=proxyip
proxyPort=3128

When performing a node fetch, If the system has a proxy set, it should use it. Based on my research it seems that this will require a new version of the fetch function

[Mionsz]

@cp-whatcha resolved in recent PR - please review and give a feedback #73