Fix panel collapsing

-Change Other networks to accordion2
-Change Other Labyrinths to accordion3

Should resolve inconsistencies in collapse and open of panels
Global sidebar for homepage

-Give homepage the global sidebar
Merge Logo & Heading classes

-Standardise page design on subpages, merge classes for #home and
#labyrinths
shared.css changes

-Tweak width for .line-roundel, introduce left margin value
-Introduce new class for panel-text.
Labyrinths changes

-Introduce placeholder header
-Make nav bar link to homepage
-Opens bug #7 - Create global navbar
Hammersmith & City line

-Complete line page for Hammersmith & City line
-Fix map links
-Gallery WIP
Metropolitan line

-Complete line page for Metropolitan line
-Minor map formatting tweaks
-Gallery WIP
Central line

-Complete line page for Central line
-Gallery WIP
Circle line

-Complete line page for Circle line
-Gallery WIP
Line page tweaks

-Corrections to Labyrinth count formatting on Cen, Cir, H&C & Met
Northern line

-Complete line page for Northern line
-Gallery WIP
Piccadilly line

-Intro for picc
-Fix map numberings
-Update gallery (WIP)
District line

-Update blurb
-Fix map link typos
-Add gallery (WIP)
Lines page

-Update all LU lines with blurb and key facts
-Add key facts and placeholder blurbs for non-LU lines
Introduce white-link class

Allows us to override red links when on a red background
Footer updates

-Add Blog to About; formatting for Help centre and Contact
-Tweak Community; remove Play/Talk, add User hub and Opportunities
-Add Legal heading to col 3; Add Copyright option
-Change column 4 to social; move logo to top, add Facebook, Twitter &
Instagram
-Add bottom copyright info for site & Labyrinth