-Cleaning

git-svn-id: https://plugins.svn.wordpress.org/wp-booklet/trunk@853677 b8457f37-d9ea-0310-8a92-e5e31aec5664
- UI enhancements
- Fixed padding reverting to 10px when set to 0
- Added test for uploads folder's writability

git-svn-id: https://plugins.svn.wordpress.org/wp-booklet/trunk@853678 b8457f37-d9ea-0310-8a92-e5e31aec5664