Document Mangement updates

This pull request includes the Document Management chapter's Control Panel and AlloyUI theme updates I was working on BEFORE the 6.2 snapshots/control panel update freeze. This finishes my initial pass of chapters 1-5 of the User Guide for Control Panel and Alloy UI updates. The Liferay Sync excess image problem is also fixed and included.

I'll recheck the validity of these updates when 6.2 UI updating is started again.

https://issues.liferay.com/browse/LRDOCS-596