Remove pictograms for now
Added word 'phase' to page titles
Add subtitles to phases pages
Make breadcrumb more explicit
Share phases list across home page and phases index page
Create phase 'tube-line' effect in CSS

Allows for indefinitely long tube lines. Needs a little work.
Refine phase line styles
Include breadcrumbs on phases layout
Add guidance links for relevant phase

Also change "class" to "phase" in front matter as it's used for more than just the class.
Sort phase links by category
Remove extraneous category
Inform if no guidance is available for phase
Split out browse links into include
Transpose phase link headings down
Delete commented phases css
Tweaks to service.gov.uk subdomain guidance

I've generally cleaned this up a bit, attempted to make parts of it more
readable, reordered sections to eliminate the need to reference requirements
that haven't yet been described, and added a few technical links and examples
where we had said we would provide them later.
Strengthen guidance on accessibility and content

A number of wording tweaks. In general I've made the guidance on accessible
formats and open standards stronger, and made clear that Léonie's guidance on
making PDFs accessible is help for a "last resort" situation, and not our
desired publication method.

In addition, I've added the cross-referencing chatted about with @psd.
phase navigation wip
reformatting and rewording of development environments
rename licencing -> licensing