When simulating SDL, the panel showing the process static data was not
updated properly with respect to the current SDL state

Conflicts:
	asn1_value_editor/resources.py

When simulating it is now possible to change the system internal state
(any DCL-declared variable). The undo and redo buttons are active to
restore any state.

The print output could pollute other scripts that import this module

It is not possible to share the stack between SDL and MSC handlers, they
live in separate threads.

When working with a dll, the API offers the possibility to return to a
previously stored global system state, enabling (infinite) undo
capability - yet to be implemented.