Update the documentation to use linking by name

See https://doc.rust-lang.org/stable/rustdoc/linking-to-items-by-name.html

libraries/persistent_store/src/model.rs

@@ -12,13 +12,16 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//! Store specification.
+
 use crate::format::Format;
 use crate::{usize_to_nat, StoreError, StoreRatio, StoreResult, StoreUpdate};
 use std::collections::HashMap;
 
 /// Models the mutable operations of a store.
 ///
-/// The model doesn't model the storage and read-only operations. This is done by the driver.
+/// The model doesn't model the storage and read-only operations. This is done by the
+/// [driver](crate::StoreDriver).
 #[derive(Clone, Debug)]
 pub struct StoreModel {
     /// Represents the content of the store.