Minor refactoring and code beautifier

[nichtich]

I moved the build_* scripts to their own directory to separate scripts and sources. The original sources (build/chapters/*?) should further be moved to their own directory, with the build directory as fully generated instead of mixed sources and generated. I also added a JavaScript code beautifier for HTML output. Right now the book is not fun to read or to contribute because you get no agile product. There should at least be a title page and a table of contents instead of a set of lonely chapters, each in its own file. The PDF is just ugly, it more looks like a proof of concept. I think with a nice title page and table of contents the book will better look like a book. Have a look at http://patterns.dataincubator.org/book/ for a nice example.