Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC 267291:
Use strcasecmp() instead of strcmp() when checking user-supplied encoding
names so that encoding names are treated as case-insensitive. This allows
the use of 'utf-8' instead of 'UTF-8' for example and matches the behavior
of iconv(1).

PR: 167977

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Use strcmp that I replaced by accident.

Remove dead code

Add unicode support to msdosfs and smbfs; original pathes from imura,
bug fixes by Kuan-Chung Chiu <buganini at gmail dot com>.

Tested by me in production for several days at work.