Links can be to named processes, convert atom to list

following the last evolution - use wxStatusBar:new(Frame) then wxFrame:setStatusBar(Frame, StatusBar), the status bar use the full space available in frame.
move the creation of the status bar after the creation of the notebook and the mainsizer.

it is ok on windows 7 64bits, no other test done so far.

crashdump_viewer would crash if the owner of a timer was specified as
the process' regisered name. This has been corrected.

wx can not catch the delete of the status bar if
it have not created it, which might cause a crash.

Ensure that the server exists on close, even though linked to the test process

Avoids wxWidgets assert if the table is empty

* dgud/observer/test:
  observer: Add simple test and add debug hooks in app

Add hooks in observer so that we can do some basic testing on it

A node to which we have references to multiple instances (creations)
will have an information line in the crashdump like this:

Creation: 1 2 ...

This would earlier crash because crashdump_viewer would try to do
list_to_integer on the value after "Creation: ". This is now
corrected.

This correction also helps the case when the emulator is debug
compiled, since the line could then be

Creation: 1 (refc=1)

crashdump_viewer:progress_pmap did sometimes hang since is spawned a
process, then monitored it and waited for a specific DOWN
message. When the process' work was very fast, it would exit before
the call to monitor and the DOWN message would contain reason 'noproc'
instead of the expected {pmap_done,Result}.

By doing spawn_monitor/1 instead, the monitor is always set before the
process exits so the deadlock is avoided.