Update services_ntpd.php

Add validation for the case of no server specified, fall back to pool.ntp.org
Improve /etc/sshd:

. Create ed25519 key for ssh and silent daemon
. Remove some exec() calls
. We do not need to re-create all keys if /root/.ssh/authorized_keys is
  empty
. Remove some redundancy and declare a single array with all keys
Fix typo
Add @ to silent any possible return of posix_kill
client-config-dir is also useful when using OpenVPN's internal DHCP while bridging.
glob() is already called by unlink_if_exists
Bring in proper gmirror support for the GUI and notifications.
Made a general gmirror library to perform various gmirror tasks and get information, using some of the former widget logic to start. Updated widget to use this new code.
Added a Diag > GEOM Mirrors page that displays information about existing mirrors and perform various management tasks. Current actions include rebuilding a drive, forgetting disconnected mirror drives, insert/remove, deactivate/activate, clearing medatada. It's now possible to use the GUI to rebuild a failed mirror by performing a forget, then insert action to replace a missing/dead drive.
Also included is a notification setup. Mirror status is polled every 60 seconds, and if any aspect of the mirror changes, notifications are issues that alert in the GUI and by SMTP, etc.
Drop a note on the page about how to repair a failed mirror.
remove openbgpd bits from system_gateways_edit and system.inc. The package
match is case-sensitive and hasn't matched the openbgpd package's name in
at least 5 years, so it doesn't do anything. It's far from functional in
any useful manner even fixing that issue.
Fix variable name
Fix filename
Merge pull request #1219 from nagyrobi/patch-13
allow ipaliases to be configured on lo0
Tidy up "crash_reporter.php" XHTML

Tidy up Paragraph tags
Close INPUT tags
Tidy up "diag_dns.php" XHTML

Move the "=" sign into the first table cell, this allows the output to
line up in the second cell,
Tidy up the table from the "resolution time" output.
Tidy up "status_openvpn.php" XHTML

Move the closing FORM tag after the PHP check if there are any OpenVPN
instances.
Tidy up "status_queues.php" XHTML

Add closing BODY and closing HTML tags if "traffic shaping is not
configured."
Merge pull request #1223 from ExolonDX/branch_master_01
Merge pull request #1224 from ExolonDX/branch_master_02
Merge pull request #1225 from ExolonDX/branch_master_03