Draft: Issue #3492478 by John Franklin: Rewrite KeyPair.php to use native OpenSSL over phpseclib.
Closes #3492478
The patch as-is removes support for anything except PEM-formatted keys and certs as that's the only thing that the native PHP OpenSSL library supports. This probably covers 90% of users, 5% of the remaining could convert from DER to PEM, and the last 5%?