edit docs for Running tab

docs/source/user/running.md

@@ -1,19 +1,23 @@
-# Running kernels and terminals
+# Managing kernels and terminals
 
-The Running List (Running tab in the Left Panel) shows a list of all the
-notebooks, code consoles and terminals that are currently running across all
+The Running tab in the left sidebar shows a list of all the kernels and
+terminals currently running across all notebooks, code consoles, and
 directories:
 
 [screenshot]
 
 As with the classic Jupyter Notebook, when you close a notebook document, code
-console or terminal, the underlying kernel or terminal running on the server
-continues to run. This allows you to perform long running actions and return
-later. The Running List allows you to re-open, or focus, the document linked to
-a given Kernel or Terminal:
+console, or terminal, the underlying kernel or terminal running on the server
+continues to run. This allows you to perform long-running actions and return
+later. The Running tab allows you to re-open or focus the document linked to
+a given kernel or terminal:
 
 [animation]
 
-Kernels or Terminals can be shutdown from the Running list:
+Kernels or terminals can be shut down from the Running tab:
 
-[animation]
+[animation]
+
+You can shut down all kernels and terminals by clicking the `X` button:
+
+[animation]