Fix all clippy warnings (#564)

* Fix all clippy warnings

* Revert usage of inclusive ranges

* Remove redundant function argument

* Revert use of unavailable pointer methods

* Introduce ContiguousCaseRange

lib/bforest/src/map.rs

@@ -284,6 +284,7 @@ where
     ///
     /// If the cursor reaches the end, return `None` and leave the cursor at the off-the-end
     /// position.
+    #[cfg_attr(feature = "cargo-clippy", allow(should_implement_trait))]
     pub fn next(&mut self) -> Option<(K, V)> {
         self.path.next(self.pool)
     }