The deployment script will enable basic-auth by default to help
avoid people deploying to a public IP with no protection from
malicious actors.

- In deploy_stash.sh /dev/random can hang on some systems, so using
  urandom will give a better experience, if less "random" data.
  For the purposes of creating an initial basic auth password this
  is sufficient.
- Alpine Linux does not have the shasum command, but sha256sum.
- Tested on MacOS with and without --no-auth flag.
- Does not apply for armhf or powershell.

BASIC_AUTH env-var added by Vivek Syngh @viveksyngh

Signed-off-by: Alex Ellis (VMware) <alexellis2@gmail.com>