Add recent changelog to README

Author: JoshData

README.md

@@ -42,10 +42,16 @@ This library was first published in 2015. The current version is 1.2.1
   be doing on all of your user inputs already!)
 * Rejecting most special-use reserved domain names. A new `test_environment`
   option is added for using `@*.test` domains.
-* New module-level attributes are added to override the default values
-  of the keyword arguments and the special-use domains list.
 * Some fixes in the tests.
 
+Unreleased changes in development:
+
+* Deliverability checks now check for 'v=spf1 -all' SPF records as a way to reject more bad domains.
+* Special use domain names now raise EmailSyntaxError instead of EmailUndeliverableError.
+* New module-level attributes are added to override the default values of the keyword arguments and the special-use domains list.
+* The keyword arguments of the public methods are now marked as keyword-only.
+* [pyIsEmail](https://github.com/michaelherold/pyIsEmail)'s test cases are added to the tests.
+
 ---
 
 Installation