previously, no cleanup would be performed, SIGINTs being catched above
the server.run() function
+ signal handler for SIGINT, SIGTERM
* put serve_forever in its own thread, to be able to call shutdown() on
the server
Change-Id: Ia5c021f3d6fd60ff2b9012c10e30715f93104977
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/31340
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Alexander Zaft <a.zaft@fz-juelich.de>
