[videodb] change country table to new layout
[videodb] change genre table to the new format
[videodb] change studio table to the new format
[videodb] change tag table to the new format
[videodb] change actor table to the new format
[videodb] factor out index creation of link tables + add missing indicies
[videodb] FIXUP fix UpdateLink(Actor)Table with main table updates
[videodb] tags can be updated using UpdateLinkTable
[videodb] cleanup and unify link table addition
[videodb] simplify the AddLinkToActor/AddToLinkTable/RemoveFromLinkTable functions
[videodb] adds Append*Filter() to simplify repetitive queries in GetFilter
[videodb] FIX: drop incorrect querying of non-existent setlinkmovie table
squish into genres - renames link table
squish into actors - renaming link table
squish into AppendFilter
squish into studio - renaming link table
squish into country - renaming link table
squish into director - renaming link table
squish into writer - renaming link table
squish into tag - renaming link table