Revert "Unbumb requirejs, causes problems with qunit + phantomjs"

This reverts commit c1e4231c5172ddc9f16903b575b36a408cb52163.
Revert "Added download link to intro presentation"

This reverts commit 502e0dc35995fef0f8ca8813a514743ca2e1c0a5.
Unbump requirejs, causes problems with qunit + phantomjs