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
Merge pull request #16 from avagin/xemul

Basic support of user namespaces, process descriptors, static version of the library, etc
lsm: borrow lsm from LXC
process: add ability to set a security label

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