Add the ability to override the default file and directory from
which certificates are loaded by setting the OpenSSL compatible
environment variables: SSL_CERT_FILE, SSL_CERT_DIR.
If the variables are set the default locations are not checked.
Added new default file "/usr/local/etc/ssl/cert.pem" for FreeBSD.
Certificates in the first valid location found for both file and
directory are added, instead of only the first file location if
a valid one was found, which is consistent with OpenSSL.
Fixes#3905Fixes#14022Fixes#14311Fixes#16920Fixes#18813 - If user sets SSL_CERT_FILE.
Change-Id: Ia24fb7c1c2ffff4338b4cf214bd040326ce27bb0
Reviewed-on: https://go-review.googlesource.com/36093
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>