Bugfix: we've configured the wrong UTCB in root.
Fixed Sc-parent-calls (we can't translate within one Pd).
Rewinded last change: Translation within one Pd works (limited)
Changed session-/service-protocol.

I've decided to do the session-creation similar to Genode, i.e.
the parent creates and destroys sessions at the service. After
thinking about and trying various other schemes, this seems to
be the only reasonable one if the parent should be able to
restrict session-creations of its childs. Because otherwise
one can't control session-parameters that easily if at all.
And this is critical IMO for things like giving a child only
access to a subtree of the filesystem. So, restricting only
the number of sessions isn't enough (which can be achieved
in a simpler way). Additionally, the whole protocol is simple.

The disadvantage is that currently the parent has to trust
the services (its childs) to a certain degree because he does
an IPC-call to them. IMO this can be solved by introducing
IPC timeouts and deadlock detection in NOVA.
Copy the elf64-binary of NOVA to bin/apps for debugging purposes
Give child of sub a different name.
Added deadlock detection and a way to give Pds a name in NOVA.
Added SListTreap and a unittest for it.
Rewrote the destruction of sessions and childs.

Now we have a general algorithm for deleting objects that may be
used on multiple CPUs. The basic idea is to invalidate an object
first, ensure that nobody is using it anymore and delete it finally.
For the two usecases that exist so far, the second step is achieved by
letting all affected Ecs call through an empty portal.

Additionally, the session portals and child portals receive directly
the pointer to the session and child object, respectively. This avoids
that we have to find that object in an efficient way from the selector.
The other consequence is thus that the number of sessions/childs is no
longer statically limited but arbitrary large (limited by the amount of
memory).

Furthermore, RCU isn't used for the destruction anymore, but we have
a class Reference now that allows us to get a session/child by id and
use it without the risk of it being deleted during that time. So, in
the portals these objects can be used as they are because they will
never be destroyed during an active portal call, but when one wants to
use them at other locations, one uses Reference (which might destroy
it in the destructor).
Added session-create and destroy unittest.
Added GlobalThread::join().

This is required to allow to wait for thread termination in a
reasonable way. That is, e.g. before terminating the main-thread
and thus the Pd, we want to wait for all other threads to
terminate to prevent that these threads cause pagefaults or
similar when they weren't completely dead yet.
Fixed bug in console.