message: doc(runtime-core) Hide some traits and structs in the documentation.
  Those are not necessary for the user. It's only internal
  implementation, that must be public because it ends up in public
  types, but the compiler infers everything automatically.
diff: @@ -118,6 +118,7 @@ pub trait WasmTypeList {
  /// This trait is never aimed to be used by a user. It is used by the
  /// trait system to automatically generate an appropriate `wrap`
  /// function.
  +#[doc(hidden)]
  pub trait HostFunctionKind {}
  /// This empty structure indicates that an external function must
  @@ -128,8 +129,11 @@ pub trait HostFunctionKind {}
  /// x + 1
  /// }
  /// ```
  +#[doc(hidden)]
  pub struct ExplicitVmCtx {}
  +impl HostFunctionKind for ExplicitVmCtx {}
  +
  /// This empty structure indicates that an external function has no
  /// `vm::Ctx` argument (at first position). Its signature is:
  ///
  @@ -140,7 +144,6 @@ pub struct ExplicitVmCtx {}
  /// ```
  pub struct ImplicitVmCtx {}
  -impl HostFunctionKind for ExplicitVmCtx {}
  impl HostFunctionKind for ImplicitVmCtx {}
  /// Represents a function that can be converted to a `vm::Func`
  