message: Fix doc comment for 3-level QuerierResult
diff: @@ -77,7 +77,10 @@ pub trait Api: Copy + Clone + Send {
  fn human_address(&self, canonical: &CanonicalAddr) -> FfiResult<HumanAddr>;
  }
  -/// A short-hand alias for the two-level query result (1. accessing the contract, 2. executing query in the contract)
  +/// A short-hand alias for the three-level query result
  +/// 1. Passing the query message to the backend
  +/// 2. Accessing the contract
  +/// 3. Executing query in the contract
  pub type QuerierResult = FfiResult<SystemResult<StdResult<Binary>>>;
  pub trait Querier: Clone + Send + 'static {
  