Redundancy-module-of-VNFFG

This blueprint is for Redundancy module of VNFFG.
The proposed module in this blueprint is a optional module to construct one more VNFFG by selecting redundancy VNFFG module.
To implement this module, we modified the get_vnf_mapping function to construct one more VNFFG. Two VNFFGs are configured so that they are maximally disjointed as possible. Therefore, we can get the result of get_vnf_mapping as new_mapping_1, new_mapping_2.
This module can be used for multiple path for load-balancing, backup VNFFG or redundant VNFFG for high availability.