fix output of listassetindex in help
fix output of listassetindex in help


Former-commit-id: 1b6be66405e70515cc476be8e7c8d1d8da6a1967
syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin