我一直在摆弄我的 Mac，试图安装自签名证书作为我们 WAN 站点的可信证书（我们无法证明为真正的签名证书付费）
我弄坏了一些东西，想知道如何恢复（如果需要的话，甚至可以从另一台 Mac 恢复，我有一台功能齐全的 Macbook 还没有弄坏，还有我同事的机器）。
以下是我尝试使用 curl 通过 SSL 下载某些内容时得到的结果：
$ brew install memcached
==> Installing memcached dependency: libevent
==> Downloading https://github.com/downloads/libevent/libevent/libevent-2.0.16-stable.tar.gz
curl: (60) SSL certificate problem, verify that the CA cert is OK. Details:
error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed
More details here: http://curl.haxx.se/docs/sslcerts.html
curl performs SSL certificate verification by default, using a "bundle"
of Certificate Authority (CA) public keys (CA certs). If the default
bundle file isn't adequate, you can specify an alternate file
using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
the bundle, the certificate verification probably failed due to a
problem with the certificate (it might be expired, or the name might
not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
the -k (or --insecure) option.
Error: Download failed: https://github.com/downloads/libevent/libevent/libevent-2.0.16-stable.tar.gz