Interchange navigation

-Introduce specific class for interchange options
-Add class for ‘Way out’
-Fix classes for Previous & Next stations, per line.
Update first thirteen Met line stations

-Introduce Interchange where missing
-Change placeholder video to placeholder image
-Link Labyrinth logo to homepage
-Add Labyrinth location hint & difficulty rating where missing
Branch colours to separate CSS

-Background colours from Shared
-Text colours from Header-Footer
-Top colours from Header-Footer

Also changes Next/Prev classes to exclude top colour
Fix Interchanges

Tweak early Met line stations to reflect updated CSS
Kings X and Heathrow T123 WIP

Edits made whilst testing spacings and alignment; not final