Beta (trunk) updates:
* Imagic thumber now correctly selects FIRST page of PDF files. TODO: determine if same can be done for other Imagick filetypes.
* Other minor enhancements.

git-svn-id: https://plugins.svn.wordpress.org/document-gallery/trunk@839474 b8457f37-d9ea-0310-8a92-e5e31aec5664