update history

History.txt

@@ -2,6 +2,8 @@
   * Major Enhancements
     * Add support for parsing git notes.
     * Add `git cat-file --batch` support with Grit::Repo#batch.
+  * Minor Enhancements
+    * Grit::Index#commit supports custom committer/author names and dates.
   * Bug Fixes
     * Zero-Padding issue in Grit::Index was fixed.