libct: add initial go bindings

This patch is a prototype. I'm going to implement all other functions,
when all of you will say that it's what we want.

Cc: Michael Crosby <crosbymichael@gmail.com>
Cc: Dmitry Guryanov <dguryanov@parallels.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
mount: add flags NOEXEC, NOSUID, NODEV, STRICTATIME

All these flags are used by libcontainer.
ct: return pid from spawn_execve()
ct: allow to set pdeathsig
libct: build a static version of the library

It will be used for libcontainer. libcontainer is used by tools,
which are executed in a container and libct may be not installed there.

Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Merge pull request #15 from avagin/xemul

Here are patches which are required for integration with libcontainer
libct: build a static version of the library

It will be used for libcontainer. libcontainer is used by tools,
which are executed in a container and libct may be not installed there.

Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
test: compile tests with -Werror -Wall
userns: add ability to set mappings of user and group IDs
ct: add support of user namespaces
makefile: make clean should clean test/ too
libct: add libct.a in gitignore

Signed-off-by: Andrey Vagin <avagin@openvz.org>
libct: add new abstraction for processes

Signed-off-by: Andrey Vagin <avagin@openvz.org>
process: add a function to create a process descriptor

Signed-off-by: Andrey Vagin <avagin@openvz.org>
ct: all function to execute smth in CT take a process descriptor

Signed-off-by: Andrey Vagin <avagin@openvz.org>
ct: use propertios from a process descriptor

Signed-off-by: Andrey Vagin <avagin@openvz.org>
libct: remove old stuff

Signed-off-by: Andrey Vagin <avagin@openvz.org>
tests: update tests accoding with new changes of API
tests: check capabilities and process ids

Signed-off-by: Andrey Vagin <avagin@openvz.org>
go: add support of process descriptors

Signed-off-by: Andrey Vagin <avagin@openvz.org>