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

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

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

Update information on obtaining libarchive sources and FreeBSD-Xlist

Update libarchive to 3.0.3

Some of new features:
- New readers: RAR, LHA/LZH, CAB reader, 7-Zip
- New writers: ISO9660, XAR
- Improvements to many formats, especially including ISO9660 and Zip
- Stackable write filters to write, e.g., tar.gz.uu in a single pass
- Exploit seekable input; new "seekable" Zip reader can exploit the Zip
Central Directory when it's available; the old "streamable" Zip reader
is still fully supported for cases where seeking is not possible.

Full release notes available at:
https://github.com/libarchive/libarchive/wiki/ReleaseNotes

Remove libarchive/archive_entry_copy_bhfi.c and libarchive/mtree.5
Add these files to FREEBSD-Xlist

MFC after: 2 weeks

Remove config_freebsd.h and add to FREEBSD-Xlist
This file is common for libarchive, cpio and tar and is going to be located
outside of contrib (lib/libarchive)

Add FREEBSD-Xlist and FREEBSD-upgrade to contrib/libarchive

MFC after: 2 weeks