HTML5/CSS Refactoring, Delete Fix, Finished images --> CSS, etc..

- Refactored File_Management_MySobekViewer and Page_Image_Upload_MySobekViewer
    - Cleaned HTML to HTML5, move to CSS3, reduce javascript, etc..
    - All buttons and tabs changed from images to CSS manufactured
- Minimum refactoring on User_AdminViewer and User_Group_AdminViewer
    - All buttons and tabs changed from images to CSS manufactured
    - ( Work will continue on these viewers after 4.0 ALPHA release )
- Refactored Preferences_MySobekViewer
    - No longer written as controls, writes directly to output stream like most other viewers
    - Moved postback code up to constructor like most other viewers
    - Cleaned HTML to HTML5, move to CSS3, reduce javascript, etc..
    - All buttons and tabs changed from images to CSS manufactured
- Changes to Delete_Item_MySobekViewer
    - Now mimics the item viewer look, like editing behaviors and metadata
    - Corrected issue with not completely cleaning existing bib/vid folders
    - Verified curators can delete all items in their collection
- Updated thumbnails at the 'ALL ISSUES' level, text not centered and wraps correctly
- All round button images and tabs subfolder removed from skin folders