Update CHANGELOG for 1.3.1 release.

Author: mattdeboard

CHANGELOG.md

@@ -1,12 +1,18 @@
-## 1.3.1 ()
-- Add
-  [univesal-argument](http://www.gnu.org/software/emacs/manual/html_node/elisp/Prefix-Command-Arguments.html)
-  possibility for `elixir-mode-iex` to run <code>iex</code> with additional
-  arguments.
-- Add Recognition for question mark (?) char syntax
-- Add (failing) test for last comment in a block (#27)
-- Update Fontify character literals as strings.
-- Update inline documentation
+## v1.3.1 - 2014/07/05
+* [#52](https://github.com/elixir-lang/emacs-elixir/pull/52) - Add CLI for running elixir-mode tests.
+* [#48](https://github.com/elixir-lang/emacs-elixir/pull/48) - Add a SMIE rule function for "def". Fixes #38 and #41
+* [#50](https://github.com/elixir-lang/emacs-elixir/pull/50) - Remove grammar clause for "fn" terminal. Fixes #7
+* [#44](https://github.com/elixir-lang/emacs-elixir/pull/44) - sigil % to ~
+* [#46](https://github.com/elixir-lang/emacs-elixir/pull/46) - Added highlight for unless and Task module
+* [#45](https://github.com/elixir-lang/emacs-elixir/pull/45) - Highlight defstruct and Actor, Base modules
+* [#40](https://github.com/elixir-lang/emacs-elixir/pull/40) - IMenu: Show ExUnit tests under heading "Tests".
+* [#37](https://github.com/elixir-lang/emacs-elixir/pull/37) - Remove needless statement
+* [#35](https://github.com/elixir-lang/emacs-elixir/pull/35) - Added simple imenu support.
+* [#32](https://github.com/elixir-lang/emacs-elixir/pull/32) - Properly make variables local
+* [#31](https://github.com/elixir-lang/emacs-elixir/pull/31) - needed for effective code-navigation via syntax-ppss
+* [#28](https://github.com/elixir-lang/emacs-elixir/pull/28) - Recognize ? char syntax
+* [#24](https://github.com/elixir-lang/emacs-elixir/pull/24) - elixir-mode-eval-on-current-buffer binding comment incorrect
+* [#22](https://github.com/elixir-lang/emacs-elixir/pull/22) - Enhance `elixir-mode-iex` to accept additional arguments
 
 ## 1.3.0 (June 24, 2013)
 - Add `elixir-mode-eval-on-region` to evalute Elixir code on the