Add changelog from previous versions

Author: viniciuschiele

CHANGELOG.rst

@@ -1,6 +1,18 @@
 Changelog
 ---------
 
+1.1.2
+++++++++++++++++++
+- Fix: apidoc.json without a url was raising an error.
+
+1.1.1
+++++++++++++++++++
+- Fix: Open files using utf-8 encoding, this prevent errors like "UnicodeDecodeError: 'ascii' codec can't decode."
+
+1.1.0
+++++++++++++++++++
+- Add support for absolute url in @api
+
 1.0.0
 ++++++++++++++++++
 - Add support to Python 2.7 (:issue:`1`). Thanks :user:`hellking4u`.