Bump version numbers and document Pym.js v1.3.1, skipping 1.3.0

Author: benlk

pym-shortcode.php

@@ -3,7 +3,7 @@
 Plugin Name: Pym Shortcode
 Plugin URI: https://github.com/INN/pym-shortcode
 Description: Adds a [pym src=""] shortcode to simplify use of NPR's Pym.js
-Version: 1.2.2
+Version: 1.3.1
 Author: The INN Nerds
 Author URI: http://nerds.inn.org/
 License: GPL Version 2 or later

readme.txt

@@ -4,7 +4,7 @@ Donate link: https://inn.org/donate
 Tags: shortcode, iframe, javascript, embeds, responsive, pym, NPR
 Requires at least: 3.0.1
 Tested up to: 4.7.3
-Stable tag: 1.2.2
+Stable tag: 1.3.1
 License: GPLv2 or later
 License URI: http://www.gnu.org/licenses/gpl-2.0.html
 
@@ -44,6 +44,11 @@ Mobile view of the WordPress post with the NPR embed using Pym Shortcode:
 
 == Changelog ==
 
+= 1.3.1 =
+
+* Update to pym.js version 1.3.1: https://github.com/nprapps/pym.js/releases/tag/v1.3.1 (Changelog at https://github.com/nprapps/pym.js/blob/master/CHANGELOG)
+* (we skipped pym.js version 1.3.0: https://github.com/nprapps/pym.js/releases/tag/v1.3.0)
+
 = 1.2.2 =
 
 * Update to pym.js version 1.2.2: https://github.com/nprapps/pym.js/releases/tag/v1.2.2 (Changelog at https://github.com/nprapps/pym.js/blob/master/CHANGELOG )