Add Ident/IdentX to AST.

RELEASES.md

@@ -24,6 +24,11 @@ New features
 * Low-level API for custom syntax allowing more flexibility in designing the syntax.
 * `Module::fill_with` to poly-fill a module with another.
 
+Enhancements
+------------
+
+* AST data structures are optimized to maximize cache friendliness. This may have speed impacts on large, complex scripts (benchmarks wanted!).
+
 
 Version 0.19.3
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