zdtm: check mappings
restore: wait all restored processes in case of failure
debug
PTRACE_O_TRACESYSGOOD
xxx
debug
log-simple: print pointers
debug messages
static/mountpoints
mounts: restero slave, shared mounts correctly

If a mount is slave and it has a shared group. crtools must convert it
in slave and only than crtools can make it shared.
initialize root before dumping mount namespace
namespace: move struct ns_id into namespace.h

It's going to be used for restoring namespaces. For example we need to
enumirate the ns_ids list for restoring mount namespaces.
mounts: allow to customize root path for cr_pivot_root

We are going to restore nested mount namespaces and we will need to
change root for each of them.
restore: add mount id-s in the ns_ids list
mounts: mark local root-s in the list of mount points

We are going to dump nested mount namespaces. All sub-namespaces will be
restored as sub-mounts in the root mount namespace. So mi->mountpoint
will be not '/' even if a mount is root for its mntns.
mounts: connect sub-root to the main root
mounts: handle propogation for the global root
mounts: bind mount one root for all namespaces

Currently we support nested mount namespaces, only if all of them have
the same root.

crtools doesn't mount root, so it should be bind-mounted for all
namespaces.
namespace: add a function to search an ns_id item by id
crtools: restore nested mount namespaces

Known issue:
* currently only namespaces with the same root is supported
* nested namespaces can be dumped and restored only if the root task
  has own mount namespace.

All nested namespaces are restored in a root namespace in temporary
directories. All mount points restored in one tree and then they are
divided into namesaces.
The task with minimal pid for each namespaces unshared mntns and
then it makes pivot_root in a proper temporary directory. All other
tasks makes setns to enter into a mount namespace of the task with
minimal pid.