add version 0.2.2

* Hide summary, splash, intro, anchor and colophon if empty (added per user-requested feature)
* Add password protection to the whole edition per user-reported bug
* Hide password-protected posts that appear within the edition from general display and from navigation bar (can't include form because it will post password to the digital edition, not the included posts)

git-svn-id: https://plugins.svn.wordpress.org/digital-edition/trunk@789488 b8457f37-d9ea-0310-8a92-e5e31aec5664