message: add a clarification about how to use the builder
diff: @@ -223,7 +223,7 @@ pub enum GateError {
  pub struct BuilderCS<F: FftField> {
  gates: Vec<CircuitGate<F>>,
  - fr_sponge_params: ArithmeticSpongeParams<F>,
  + sponge_params: ArithmeticSpongeParams<F>,
  public: usize,
  lookup_tables: Vec<LookupTable<F>>,
  runtime_tables: Option<Vec<RuntimeTableCfg<F>>>,
  @@ -504,7 +504,7 @@ impl<F: FftField + SquareRootField> BuilderCS<F> {
  gates,
  shift: shifts.shifts,
  endo,
  - fr_sponge_params: self.fr_sponge_params,
  + fr_sponge_params: self.sponge_params,
  lookup_constraint_system,
  precomputations: domain_constant_evaluation,
  };
  @@ -530,14 +530,19 @@ impl<F: FftField + SquareRootField> ConstraintSystem<F> {
  /// - `lookup_tables: vec![]`,
  /// - `runtime_tables: None`,
  /// - `precomputations: None`,
  + ///
  + /// How to use it:
  + /// 1. Create your instance of your builder for the constraint system using `crate(gates, sponge params)`
  + /// 2. Iterativelly invoke any desired number of steps: `public(), lookup(), runtime(), precomputations()``
  + /// 3. Finally call the `build()` method and unwrap the `Result` to obtain your `ConstraintSystem`
  #[must_use]
  pub fn create(
  gates: Vec<CircuitGate<F>>,
  - fr_sponge_params: ArithmeticSpongeParams<F>,
  + sponge_params: ArithmeticSpongeParams<F>,
  ) -> BuilderCS<F> {
  BuilderCS {
  gates,
  - fr_sponge_params,
  + sponge_params,
  public: 0,
  lookup_tables: vec![],
  runtime_tables: None,
  