Compatibility upgrade with WooCommerce 2.1+ and some minor visual fixes.
jQuery fix for no eBooks case.

git-svn-id: https://plugins.svn.wordpress.org/editionguard-for-woocommerce-ebook-sales-with-drm/trunk@869232 b8457f37-d9ea-0310-8a92-e5e31aec5664