[NRRPLT-8168] NRP v4 Release

* [NRRPLT-8168] Advanced version to 1.3.1 and updated changelog
* [NRRPLT-8803] Acknowledgments in README.md
* [NRRPLT-0000] Revert buil script
* [NRRPLT-8168] Fix Templates for the 4.0
* [NRRPLT-8168] Templates for the 4.0
* [NRRPLT-8168] Add templates to the image
* [NRRPLT-8168][NRRPLT-8740] Clear blocked signals mask in forked processes. Increase forked processes polling time to 500ms.
* [NRRPLT-8168] Rename configuration atribute from "SimDescription" to "SimulationDescripion" in experiments
* [NRRPLT-8168] Add template experiment
* [NRRPLT-8168] Unmask signals in engine servers launched by BasicFork. SIGTERM (shutdown command), SIGINT, SIGHUP (parent has died) are expected to be received so be sure they are unblocked.

Approved-by: Ugo Albanese