Fix broken link to ipython-tutorial page

Author: Chris Jeong

assignments/2017/assignment1.md

@@ -61,7 +61,7 @@ After you have the CIFAR-10 data, you should start the IPython notebook server f
 `assignment1` directory, with the `jupyter notebook` command. (See the [Google Cloud Tutorial](http://cs231n.github.io/gce-tutorial/) for any additional steps you may need to do for setting this up, if you are working remotely)
 
 If you are unfamiliar with IPython, you can also refer to our
-[IPython tutorial](/ipython-tutorial).
+[IPython tutorial](/ipython-tutorial.md).
 
 ### Some Notes
 **NOTE 1:** This year, the `assignment1` code has been tested to be compatible with python versions `2.7`, `3.5`, `3.6` (it may work with other versions of `3.x`, but we won't be officially supporting them). You will need to make sure that during your `virtualenv` setup that the correct version of `python` is used. You can confirm your python version by (1) activating your virtualenv and (2) running `which python`.