RFC: minijail: add libminijail.

Drewry requested an implementation of minijail that:

1) Would be linkable against C programs
2) Not depend on libbase
3) Supply the necessary LD_PRELOAD hacks to use his syscall-filtering framework
   without the apply-after-exec hack and to use ptrace-disable.

Thoughts?

BUG=chromium-os:17937
TEST=Adhoc (extremely ;)). Proper test suite to be written; crosbug.com/18834

Change-Id: I8b34557a9a231dad75827c1a3d11f235f712648d
Signed-off-by: Elly Jones <ellyjones@chromium.org>
Reviewed-on: http://gerrit.chromium.org/gerrit/4585
Reviewed-by: Will Drewry <wad@chromium.org>
7 files changed