Docs: remove Atom from the list of recommended editors (#6388)

docs/guide_cog_creation.rst

@@ -55,7 +55,7 @@ the purposes of this example, we'll call this :code:`mycog`).
 In this folder, create three files: :code:`__init__.py`,
 :code:`mycog.py`, and :code:`info.json`. Open the folder in
 a text editor or IDE (examples include `Sublime Text 3 <https://www.sublimetext.com/>`_,
-`Visual Studio Code <https://code.visualstudio.com/>`_, `Atom <https://atom.io/>`_, and
+`Visual Studio Code <https://code.visualstudio.com/>`_, and
 `PyCharm <http://www.jetbrains.com/pycharm/>`_).
 
 .. attention::