htmlnotebook doc updates

* Indicate that MathJax will be loaded from CDN by default
* add missing markdown link and 
* a few typos

docs/source/install/install.txt

@@ -352,22 +352,26 b' MathJax'
 -------
 
 The IPython notebook uses the MathJax [MathJax]_ Javascript library for rendering LaTeX
-in web browsers. Because MathJax is large, we don't include it with IPython. We do, however,
+in web browsers. Because MathJax is large, we don't include it with IPython. Normally
+IPython will load MathJax from a CDN, but if you have a slow network connection, or
+want to use LaTeX without an internet connection at all, we do
 include a utility to aid in downloading MathJax and installing it into the proper location::
 
     from IPython.external.mathjax import install_mathjax
     install_mathjax()
 
+This function does require write access to the IPython install directory, so if you
+have a system-wide Python install, it may need to be done from a ``sudo python`` session.
 
-Browser Compatiblity
---------------------
+Browser Compatibility
+---------------------
 
 The notebook uses WebSockets and the flexible box model. These features are
 available in the following browsers:
 
 * Chrome.
 * Safari.
-* Firefox 4 and 5. These browesrs have WebSocket support, but it is disabled by
+* Firefox 4 and 5. These browsers have WebSocket support, but it is disabled by
   default. You can enable it by entering ``about:config`` in the URL bar and then
   setting ``network.websocket.enabled`` and ``network.websocket.override-security-block``
   to ``true``.

docs/source/interactive/htmlnotebook.txt

@@ -62,7 +62,7 b' A notebook is a combination of two things:'
 1. an interactive session connected to an IPython kernel, controlled by a web
 application that can send input to the console and display many types of output
 (text, graphics, mathematics and more).  This is the same kernel used by the
-:ref:`Qt console <qt_console>`, but in this case the web console sends input in
+:ref:`Qt console <qtconsole>`, but in this case the web console sends input in
 persistent cells that you can edit in-place instead of the vertically scrolling
 terminal style used by the Qt console.
 

docs/source/links.rst

@@ -72,3 +72,4 b''
 .. _indefero: http://www.indefero.net
 .. _git: http://git-scm.com
 .. _github: http://github.com
+.. _MarkDown: http://daringfireball.net/projects/markdown/