Update Changelog

Author: Aster89

Changelog

@@ -1,4 +1,9 @@
-Unreleased changes:
+Changed in version 0.8.4.1:
+
+   * Implemented ; and , movements and enabled them for d, c, and y actions.
+
+   * Internal refactoring of f, F, t, T commands to allow implementation of ;
+     and , commands.
 
 Changed in version 0.8.4.0:
 
@@ -43,6 +48,7 @@ Changed in version 0.8.1.0:
 Changed in version 0.8.0.1:
    * Add a Cabal flag to disable the example executable as well as
      the test that uses it.
+
 Changed in version 0.8.0.0:
    * Breaking changes:
      * Add a `MonadFail` instance for `InputT`.