CHANGELOG.md in ndr_support-5.5.1 vs CHANGELOG.md in ndr_support-5.6.0

@@ -1,7 +1,11 @@
 ## [Unreleased]
 *no unreleased changes*
 
+## 5.6.0 / 2019-08-29
+### Added
+* Add `Integer#working_days_since`. (#11)
+
 ## 5.5.1 / 2019-05-15
 ### Fixed
 * Support Ruby 2.6, Rails 6.0. Minimum Ruby/Rails versions are now 2.5/5.2
 * Warn when WorkingDays lookup is getting stale
 * Improved date parsing in String#to_date