write changelog and add myself to credits

CHANGES.rst

@@ -6,11 +6,14 @@ Changelog
 
 Breaking changes:
 
-- *add item here*
+- icalendar now longer accepts -o as an option
+- icalenar now takes a ics file directly as an input
+- icalendar's output is different
 
 New features:
 
-- *add item here*
+- icalendar utility outputs a 'Duration' row
+- icalendar can take multiple ics files as an input
 
 Bug fixes:
 

docs/credits.rst

@@ -56,6 +56,7 @@ icalendar contributors
 - Clive Stevens <clivest2@gmail.com>
 - Dalton Durst <github@daltondur.st>
 - Kamil Mańkowski <kam193@wp.pl>
+- jacadzaca <vitouejj@gmail.com>
 
 Find out who contributed::