Add satisfiability check to validate(Authority)
Add satisfiability check to validate(Authority)

Add a check to the validate function on authority which checks that the
authority can be satisfied, which is to say, that the total of all the
weights meets or exceeds the threshold.

EOSIO/eos,EOSIO/eos,EOSIO/eos,EOSIO/eos,EOSIO/eos