Got PDF book working.

Converted format of all notebooks so they can be processed with nbconvert.
Wrote a build_book script that merges the notebook and creates book.pdf

styles/custom2.css

@@ -29,7 +29,6 @@
     } 
     h2 {
         font-family: 'Open sans',verdana,arial,sans-serif;
-        text-indent:1em;
     }
     .text_cell_render h2 {
         font-weight: 200;