Issue #2502: Add line break after The Jupyter Notebook is running at: (#2505)

* Issue #2502: Add line break after The Jupyter Notebook is running at:

* Revert "Issue #2502: Add line break after The Jupyter Notebook is running at:"

This reverts commit 3aa65e712006f2726ea57476dd8923753a13e4ef.

* Issue #2502: Reverted previous changes and redone without strip trailing spaces

docs/source/security.rst

@@ -31,7 +31,8 @@ When you start a notebook server with token authentication enabled (default),
 a token is generated to use for authentication.
 This token is logged to the terminal, so that you can copy/paste the URL into your browser::
 
-    [I 11:59:16.597 NotebookApp] The Jupyter Notebook is running at: http://localhost:8888/?token=c8de56fa4deed24899803e93c227592aef6538f93025fe01
+    [I 11:59:16.597 NotebookApp] The Jupyter Notebook is running at:
+    http://localhost:8888/?token=c8de56fa4deed24899803e93c227592aef6538f93025fe01
 
 
 If the notebook server is going to open your browser automatically

notebook/notebookapp.py

@@ -1353,7 +1353,8 @@ class NotebookApp(JupyterApp):
         "Return the current working directory and the server url information"
         info = self.contents_manager.info_string() + "\n"
         info += "%d active kernels \n" % len(self.kernel_manager._kernels)
-        return info + "The Jupyter Notebook is running at: %s" % self.display_url
+        # Format the info so that the URL fits on a single line in 80 char display
+        return info + "The Jupyter Notebook is running at:\n\r%s" % self.display_url
 
     def server_info(self):
         """Return a JSONable dict of information about this server."""