Added SystemC Contribution

Name: Added SystemC input for O7.2.1
Description: Added SystemC input for O7.2.1
Gist URL: -
Cryptography: No
Author(s): Alexander Nitsch (URO), Benjamin Beichler (URO), Stefan Rieger (TWT)

I hereby declare that I accept to contribute following the openETCS terms of use and the openETCS IP policy.