First cut at TDLR-516.  TBD - move login link to footer, remove auto create in user table, add dark archive config value and customizations.
Moved the login link from the navbar to the footer;  made an error message a little better;  added download hi-res link to image_texts and wps;  users must be manually added to the users table (via admin page).
Folded Dark Archive features into TDL, which can be activated by changing a new config setting.