UI / UX improvements regarding processed data

[phirstgemini]

• In /download tarball, only put files in subdirectory if there's a name clash
• Make processing column more concise, just Raw, QL, SQ, with tool tip showing acronym and processing tag. Make this a default column. Move history and reduction info links into this column
• Add an optional processing tag column, value link to processing tags page.
• Add a link to the processing tags list page on the searchform next to the pulldown