Update changelog for 1.3.2.2

changelog.md

 Changelog for the [`directory`][1] package
 ==========================================
 
+## 1.3.2.2 (April 2018)
+
+  * Relax `base` version bounds to support 4.12.
+
 ## 1.3.2.1 (March 2018)
 
   * Relax `Win32` version bounds to support 2.7.

directory.cabal

 name:           directory
-version:        1.3.2.1
+version:        1.3.2.2
 -- NOTE: Don't forget to update ./changelog.md
 license:        BSD3
 license-file:   LICENSE