Release version 4.0.1 (#691)

* Add CHANGELOG entries so far

* v4.0.1

Author: isaacbrodsky

Diff for: CHANGELOG.md

@@ -6,8 +6,24 @@ The public API of this library consists of the functions declared in file
 [h3api.h.in](./src/h3lib/include/h3api.h.in).
 
 ## [Unreleased]
+
+## [4.0.1] - 2022-09-15
 ### Fixed
 - Changing an internal `float` to `double` improves the precision of geographic coordinate output (#652)
+- Fixed compacting all children of a resolution 0 cell (#679)
+- Fixed possible signed integer overflow in `maxGridDiskSize` (#686)
+- Fixed possible use of uninitialized values in `cellToVertex` (#683, #690)
+- Fixed possible out of bounds read in `localIjToCell` (#684)
+- Fixed possible memory leak in `compactCells` (#685)
+- Fixed possible out of bounds read in `areNeighborCells` (#677)
+- Fixed possible memory leak in `cellsToLinkedMultiPolygon` (#673)
+
+### Changed
+- Build script does not use toolchain file (#641)
+- Removed a duplicated include preprocessor directive (#682)
+- Improvements to the fuzzer suite and their automatic runs in CI (#671, #674, #687)
+- Increased test coverage (#642)
+- Added a fuzzer targetting internal `algos.c` functions (#675)
 
 ## [4.0.0] - 2022-08-23
 ### Breaking changes

Diff for: VERSION

@@ -1 +1 @@
-4.0.0
+4.0.1