Option to kill RAFCON if execution cannot be stopped

[franzlst]

After stopping the execution, it might happen that a thread does not join. If RAFCON is closed, the prevents the process from being stopped.

If the execution is still active after a certain amount of time, the user should have the option that the process is killed (os.exit()).

added by @Rbelder:

• so a dialog should be open if the engine is not stopping within a certain duration which offers
  • to let the thread and process life (but with a note how to kill it in the console later)
  • or to directly kill it by os.exit()
• additional sub-task would be to check if the same interface is possible for core only and to implement it in e.g. the interface-module which is in core and gui sub-package

Originally created by @franzlst ([email protected]) at 2018-05-02 11:29:15+00:00 (moved from RMC internal repository)

[franzlst]

See also: #512

Originally created by @franzlst ([email protected]) at 2018-05-02 11:29:29+00:00 (moved from RMC internal repository)