Add threshold percentage

bsip-0084.md

@@ -59,6 +59,7 @@ The flag must not be used before the time of the hardfork.
 * `unsigned_int num_members` - the number of authority members to vote on if fixed, or 0 otherwise
 * `unsigned_int min_members` - the minimum number of authority members to elect, or 0 if fixed
 * `unsigned_int max_members` - the maximum number of authority members that can be elected, or 0 if fixed
+* `uint16_t threshold` - the threshold scaled percentage of weighter member approvals required for authority approval
 * `flat_set<account_id_type> candidates` - a list of candidates eligible for voting, or empty
 * `optional<asset> candidates_hold_min` - an asset and minimum amount of it that candidates must hold to be eligible for voting
 * `bool proxy_allowed` - indicates if proxy voting is allowed
@@ -70,6 +71,7 @@ The operation must not be used before the time of the hardfork.
 
 * `creator` must exist, must have lifetime membership, and must have sufficient balance to pay the fee.
 * `voting_asset` must exist and must have the `voting_allowed` flag set.
+* `threshold` must be in the range `1..GRAPHENE_100_PERCENT`
 * If `num_members` is 0 then `min_members` and `max_members` must both be positive.
 * If `num_members` is positive then both `min_members` and `max_members` must equal 0.
 * If `candidates` is not empty then