DragonFly Variant Symlinks port

[bu7cher]

Hi, All!

I have make the port of DragonFly BSD Variant Symlinks. (http://www.freebsd.org/projects/ideas/#p-magicsymlinks)
Pathes for CURRENT can be founded on http://butcher.heavennet.ru/patches/kernel/varsym/. This is first version and i think that work in not complete.
Port is not fully identical with dfbsd implementation. Syscall interface has been changed (removed messages-related things and some parameters changed to pointers).
ToDo: 
1. src/sys/i386/i386/machdep.c - this initialization needed for each platforms?
2. I think that here needed some locking implementation.
3. Document new syscalls.

Any comments?
--
WBR, Andrey V. Elsukov