Replace interfaces-mapping with tags if possible:
! depends on new API in VPP (interface tags dump simmilar to dump_interface_table but with tags, the older api might be extended with tags)

• mappings should be avoided if possible. probably tags can be used to store aditional information
• fix implementation for interfaces, subinterfaces... (everything that has something in common with interface name mappings)
• ? fix Unit and CSIT tests (might not be needed, should be just internal change)
• ? should resolve operational state bugs (HC2VPP-310, HC2VPP-391)