update changelog and bump version

doc/changelog.md

@@ -1,5 +1,49 @@
 # Changes
 
+## v1.6.5 (16 December 2024)
+
+- New: measure CPU time alongside wall time for experiments #275
+
+## v1.6.4 (5 April 2023)
+
+- New: GitHub Actions for CI #171
+- New: add ruby 3.1 support #175
+- Fix: `compare_errors` in docs #178
+- Fix: remove outdated travis configs #179
+- Fix: typos #191
+- New: add support for `after_run` blocks #211
+
+## v1.6.3 (9 December 2021)
+
+- Fix: improve marshaling implementation #169
+
+## v1.6.2 (4 November 2021)
+
+- New: make `MismatchError` marshalable #168
+
+## v1.6.1 (22 October 2021)
+
+- Fix: moving supported ruby versions from <=2.3 to >=2.6 #150
+- Fix: update docs to explain timeout handling #159
+- New: add support for comparing errors #77
+
+## v1.6.0 (8 March 2021)
+
+- Fix: clarify unit for observations #124
+- New: enable support for truffleruby #143
+- Fix: don't default experiment when included in a module #144
+
+## v1.5.0 (8 September 2020)
+
+- Fix: clearer explanation of exception handling #110
+- Fix: remove unused attribute from `Scientist::Observation` #119
+- New: Added internal extension point for generating experinet results #121
+- New: Add `Scientist::Experiment.register` helper #104
+
+## v1.4.0 (20 September 2019)
+
+- New: Make `MismatchError` a base `Exception` #107
+
 ## v1.3.0 (2 April 2019)
 
 - New: Drop support for ruby <2.3

lib/scientist/version.rb

@@ -1,3 +1,3 @@
 module Scientist
-  VERSION = '1.6.4'
+  VERSION = '1.6.5'
 end