pfSense

Cleanup unused code:

- Remove xmlrpcbaseurl from globals
- Remove xmlrpcpath from globals
- Remove embeddedbootupslice from globals
- Remove call_pfsense_method()
- Remove check_firmware_version()
- Remove get_active_xml_rpc_base_url()
- Remove zeromq.inc...

Rework installpkg and uninstallpkg scripts to use pfSense-upgrade

Remove all PBIs before upgrade to 2.3, it fixes #5221

Disable zero copy buffers in bpf.

This was a no-op before my changes (so this was never really enabled) and
now it is known to cause issues with tcpdump and hostapd.

Disable this until we fix all the raised issues.

Issue: #5257

Use _echo, not echo

Comment typo

Fixed #5316

Validate that the Mobile Client settings have a valid RADIUS server selected
as the source for user authentication when EAP-RADIUS is selected as the
phase 1 authentication method for mobile IPsec. Fixes #5219.

Fix the captive portal rules after 98bf4991dc31f97fc7315a6b8aba433de9d39cea.

The malformed rules breaks the parsing of initialisation rules.

Issue: #4746

Fixed #5315
Converted to jQuery and added functionality to edit/save alternate URL