docs(changelog): add entry for Int.range

Author: glennsl

CHANGELOG.md

@@ -24,6 +24,7 @@
 - Fixed type signatures of `reduce` and `reduceWithIndex`. https://github.com/rescript-association/rescript-core/pull/49
 - Add `panic`/`Error.panic`. https://github.com/rescript-association/rescript-core/pull/72
 - The globally available `null` value now originates from `Nullable` and not `Null`, just like the globally available `undefined` value does. https://github.com/rescript-association/rescript-core/pull/88
+- Add `Int.range` and `Int.rangeWithOptions`, https://github.com/rescript-association/rescript-core/pull/52
 
 ### Documentation