pfSense

As a continuation of https://redmine.pfsense.org/issues/4206 I have made some bug fixes.
They address the following issues:

• Fix indexing of $mappings: Remove "$entry['iaid'] . " from $mappings[] since the IAID of the IA_NA does not need to be equal to the IAID of the IA_PD, please see note in https://redmine.pfsense.org/issues/4206#note-9
  This makes sure that Routed To in Delegated Prefixes can be shown even when the IAID of the IA_NA != to the IAID of the IA_PD.

• Fix column headers: Add table header for the icon in the Delegated Prefixes section to fix alignment of the column headers.

• Fix lack of incrementation of index in parse_duid() when two characters have been combined and passed (meaning \\ and \") for use in the IAID and DUID strings.

• Fix check in parse_duid() of $n so that the octal value is checked as an octal value and not with is_numeric($n).

• Fix substr mistake: I made a silly mistake in extract_duid() and overlooked an important difference between javascript substring() and php substr().

• Tightened regex check for octal value in extract_duid().

• Fix missing check for $active to avoid creating a route to a released lease.

I will link to the pull request in a moment.