documented changes in CHANGES and README file

Author: aRkedos

CHANGES

@@ -6,6 +6,7 @@ Here you can find the recent changes to tmuxp
 
 current
 -------
+- :issue:`589` added option for the the confirm command to auto-confirm the prompt.
 - :issue:`623` Move docs from RTD to self-serve site
 - :issue:`623` Modernize Makefiles
 - :issue:`623` New development docs

README.rst

@@ -105,6 +105,28 @@ Snapshot your tmux layout, pane paths, and window/session names.
 
 See more about `freezing tmux`_ sessions.
 
+
+Convert a session file
+----------------------
+
+Convert a session file from yaml to json and vice versa.
+
+.. code-block:: sh
+
+   $ tmuxp convert filename
+
+This will prompt you for confirmation and shows you the new file that is going
+to be written.
+
+
+You can auto confirm the prompt. In this case no preview will be shown.
+
+.. code-block:: sh
+
+   $ tmuxp convert -y filename
+   $ tmuxp convert --yes filename
+
+
 Docs / Reading material
 -----------------------