[FCL-380] Version 1 and searchbox homepage

[Donna-H]

Changes in this PR:

Implement V1 (topline nav), search box and browse updates as new homepage

Jira

FCL-380

Next steps

• Remove homepage variant Waffle tags from the service

Screenshots of UI changes:

Before

After

[jacksonj04]

I'm concerned about the number of entirely cosmetic CSS changes here; is stylelint running (or not running) in some weird way?

cc @jlhdxw

[Terry-Price]

Purely from a visual point of view it looks good @Donna-H

[jacksonj04]

A few bits in the code itself which need tidying up - we should be removing anything in these templates which relies on Waffle (ie the {% flag %} tags), as well as renaming anything which relies on variant-* in CSS or variables.

We should also remove the Waffle stuff in context_processors.py, the entire waffle_flags function can be deleted here, along with checking that references to waffle_flags in template contexts are removed, and removing judgments.context_processors.waffle_flags from the context processors in base.py.

I've added a checkbox to the PR to remind us to remove the flags themselves from the config when this is done; you might want to remove them locally first to check what happens in your dev environment when they're missing.

[jacksonj04]

If we rebase this after merging in the tidying of unnecessary compiled assets then we shouldn't need this line, since it was only relevant for the compiled CSS.