(cherry picked from commit 26c4239a)

(cherry picked from commit 78384b58)

(cherry picked from commit 1604bcf3)

(cherry picked from commit d8ab1f0d)

(cherry picked from commit b1743ce6)

(cherry picked from commit e13ed06f)

(cherry picked from commit 3604b422)

(cherry picked from commit 15c1a325)

(cherry picked from commit 89e80a4c)

(cherry picked from commit 7f75ddb8)

(cherry picked from commit ec7936c1)

(cherry picked from commit 88f49954)

(cherry picked from commit 2278a4fa)

(cherry picked from commit 770d30b5)

(cherry picked from commit 3f243e14)

(legacy, ipsec) flip ipv4/ipv6 subnet in ipsec phase2, closes https://github.com/opnsense/core/issues/446

(cherry picked from commit d0940e86)

(cherry picked from commit a7092d56)

(cherry picked from commit f1bb36ee)

(cherry picked from commit 805a739a)

(cherry picked from commit c8437ad6)

(cherry picked from commit 27f350c2)

(cherry picked from commit 0377f9e3)

(Captiveportal, new) send Content-Type on template download, chrome still ignores the Content-Disposition tag

(cherry picked from commit bb6e5520)

(cherry picked from commit 65975750)

more info : https://forum.opnsense.org/index.php?topic=1562.msg4811#msg4811

todo: remove rest of auth funcions with overlapping functionality in auth.inc

(cherry picked from commit 32ab2367)

(cherry picked from commit 21d0227e)

(cherry picked from commit 06f5db67)

(cherry picked from commit 3cfac591)