Update docs/source/interactive/htmlnotebook.txt

Added a section on configuration. Still need to add a link to the general configuration page.

docs/source/interactive/htmlnotebook.txt

@@ -243,6 +243,19 b' and then on any cell that you need to protect, use::'
   if script:
     # rest of the cell...
 
+Configuration
+-------------
+
+The IPython notebook server can be run with a variety of command line arguments. 
+To see a list of available options ehter:
+
+  $ ipython help notebook
+
+Defaults for these options can also be set by creating a file named 
+ipython_notebook_config.py in you IPython profile folder. The profile folder is
+a subfolder of your IPython directory (`ipython locate` will show you where that
+is). 
+
 Keyboard use
 ------------