Added use of more accessible tags to create tabbed-interfaces then
updated css and JS to require use of those attributes rather than custom
techniques.
Updated relevant parts of app.
Some custom parts using their own tabs though, something to improve in
future.
- Primarily moved and re-organised view files.
- Included readme within views to document the convention.
- Fixed some issues with page field select list in previous commit.
- Tweaked some route names while going through.
- Split some views out further.
Closes#2805
