Make code more DRY between widget and shortcode repeated code

git-svn-id: http://plugins.svn.wordpress.org/google-bookshelves/trunk@681382 b8457f37-d9ea-0310-8a92-e5e31aec5664
Add widgettitle class

git-svn-id: http://plugins.svn.wordpress.org/google-bookshelves/trunk@681383 b8457f37-d9ea-0310-8a92-e5e31aec5664
Fix Widget title to fit into any theme, make link to author open in new tab

git-svn-id: http://plugins.svn.wordpress.org/google-bookshelves/trunk@681384 b8457f37-d9ea-0310-8a92-e5e31aec5664
Change version to 2.1.2

git-svn-id: http://plugins.svn.wordpress.org/google-bookshelves/trunk@681385 b8457f37-d9ea-0310-8a92-e5e31aec5664
Version 2.2 update