Docs: update header format on TODO

Author: tony

TODO

@@ -3,7 +3,7 @@ TODO
 
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 - `Issue #15`_ - Pane ordering
@@ -33,9 +33,9 @@ Done
 - Assure ``$ tmuxp freeze`` works with ``start_directory`` and does not
   return commands with dir and no CD's. (esp with zsh).
 
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 - ``tmuxp freeze`` add autogenerated command to yaml configs (won't work w/ json)
@@ -60,9 +60,9 @@ Done
 - Test and ensure correct pane. https://github.com/tony/tmuxp/issues/15.
 - :ref:`about tmux` page.
 
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 - Automatically grab ``[-L socket-name]`` and ``[-S socket-path]``