added missing changelog & updated for release

Changelog.rst

@@ -0,0 +1,35 @@
+.. _changelog:
+
+================
+ Change history
+================
+
+.. _version-0.3.0:
+
+0.3.0
+=====
+:release-date: 15 Jun, 2023
+:release-by: Asif Saif Uddin
+
+- Drop Python 2 support, remove six.
+- Uses PromptSession() class from prompt_toolkit instead of prompt() function (#63).
+- Added filter for hidden commands and options (#86).
+- Added click's autocompletion support (#88).
+- Added tab-completion for Path and BOOL type arguments (#95).
+- Added 'expand environmental variables in path' feature (#96).
+- Delegate command dispatching to the actual group command.
+- Updated completer class and tests based on new fix#92 (#102).
+- Python 3.11 support.
+
+
+
+.. _version-0.2.0:
+
+0.2.0
+=====
+:release-date: 31 May, 2021
+:release-by: untitaker
+
+- Backwards compatibility between click 7 & 8
+- support for click 8 changes
+- Update tests to expect hyphens