The io/ioutil package has been deprecated as of Go 1.16 [1]. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.
Reference: https://golang.org/doc/go1.16#ioutil
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
Previously the CLI could only find the HTTP auth token when running
the CLI outside the sandbox, not like
/Applications/Tailscale.app/Contents/MacOS/Tailscale when that was
from the App Store.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>