Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

Remove 'All Rights Reserved' from xlocale FreeBSD Foundation copyrights

Sponsored by: The FreeBSD Foundation

Fix strcasecmp_l() and strncasecmp_l() POSIX 2008 compliance.

POSIX.1-2008 specifies that those two functions should be declared by
including <strings.h>, not <string.h> (the latter only has strcoll_l()
and strxfrm_l()):

http://pubs.opengroup.org/onlinepubs/9699919799/functions/strcasecmp.html

Obtained from: DragonFlyBSD
Reviewed by: theraven
MFC after: 2 weeks