create-remix support for HTTP proxies

[guigui64]

Scripts such as create-remix use node-fetch for downloading the templates from the Github API.
Unfortunately, node-fetch does not support HTTP(S) proxies.

However, there are some elegant solutions to this such as using global-agent:
https://github.com/gajus/global-agent

That way, the users of the script will only need to export environment variables to be able to use them behind proxies.

[cliffordfajardo]

@guigui64 - Does this recent pull request solve your proposed solution?
feat(create-remix): Add proxy support in create cli #4159