pfSense

Fix random typos

Image upload validation improvements. Fixes #9804

• Make functions for validating images against a pre-defined list of
  approved types
• Change the picture widget to use these functions
• Add validation for uploaded Captive Portal logo/background images

Removed escaping of CSS classes

Initialize JSON data to avoid warning.

Avoid warning/error for not initialized JSON variable.

Fix malformed JSON

Fix malformed JSON using json_encode().

Revise regex and redirect on failure

Fixed #9731
by validating widget key with regex

Incorporate filter_log.inc into syslog.inc. Issue #8350

Now all log-related functions are together.

Fix copyright message years to reflect BSDP -> ESF -> Netgate

Normalize some copyright messages