Merge pull request #101 from abought/add_requirements

Add requirements.txt to gh-pages branch

README.md

@@ -73,13 +73,13 @@ the `gh-pages` branch of their lesson website.  To do this:
 
 1. [Install Pandoc](http://www.pandoc.org/installing)
 
-2. Install pandocfilters, a Python module that helps with writing
-   filters for Pandoc:
-
+2. All Python packages required for lesson creation and validation can 
+   be installed using:
+   
     ~~~
-    $ pip install pandocfilters
+    $ pip install -r requirements.txt
     ~~~
-
+        
 3. To convert Markdown files into HTML pages in the root directory, go
    into the root directory of your lesson and run: