Unable to download files, certificate verify failed

Problem
Rustup has no option to disable certificate checking. The place I work at has networking hardware in place that basically breaks SSL. I've tried adding --no-check-certificate and --insecure to the curl/wget commands in the "easy" rustup-init.sh script, but then the rustup command fails due to the same SSL certificate validation errors. A no-nonsense get.

Steps

1. Find a company that intercepts SSL connections.
2. Try rustup-init.sh with curl and wget commands modified to not check executable. Fail because rustup checks the certificate.
3. Try installing using apt-get rustc. Fail because rustup needs to get run (eg rustup install stable) to install a toolchain, and there is no way to bypass the SSL certificate check.

Possible Solution(s)
Add a command line argument that bypasses the SSL certificate check. I've seen the other issues saying to add certificates to the ca cert folder, but there is no certificate available to add to the cert store.

Notes
Adding a command line argument to disable checking certificates is the simplest solution for a user in a restrictive corporate network that just wants a way to get a functional install of rust. It should not be as painful as it currently is; this is a useability bug, that makes for a very bad user experience when your computer is on a corporate network.

Start with the rustup-init.sh download commands and the subsequent rustup install stable flow described in the issue. Review the discussion before choosing an approach, since certificate bypassing affects both installation and toolchain downloads. Done means the proposed command-line option consistently handles the reported certificate failures without breaking normal verification.