add configure flags for setting droppriv user/group

In order to override the default user/group, you have to append your
CPPFLAGS before compiling.  Since you also have to pass along double
quotes, it can get ugly/messy fast in shell (due to the escaping).
Plus, the existing code always defines UNPRIV_USER to "nobody" which
leads to compile time warnings.

Add dedicated configure flags to make the interface simple for people
to control.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Merge pull request #58 from vapier/master

add configure flags for setting droppriv user/group
Add Seccomp-BPF policies to the repo.

These policies can be used with the Minijail tool
(http://git.chromium.org/gitweb/?p=chromiumos/platform/minijail.git)
to achieve kernel attack surface reduction.

(Also fix some trailing whitespace.)

BUG=chromium-os:36653
TEST=None

Change-Id: I35dd74702f7dfd701c86e1b25b0831d3925fbf96
Signed-off-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Merge pull request #59 from jlucangelio/add-seccomp-bpf-policies-v2

Add Seccomp-BPF policies to the repo. This needs documentation for use and so on.
Add changes by Jorge Lucangeli Obes to CHANGELOG
Add TODO items
Use /etc/tlsdate/ca-roots/tlsdate-ca-roots.conf for certs by default; allow setting file or dir
remove TÜRKTRUST from CA list post sub-ca mistakes
Update CHANGELOG
Merge branches 'master' and 'debian-master' into debian-master