[Hart] basic Hart cobranding

Originally copied from template of Bromley code, substituting logo,
council ID, geolocation data, and renaming .scss variables etc.

(NB: this was a bad idea.  As per notes/cobranding.txt, should have
started with less copying of files, as this required more cleanup.
Bromley's code has some particularities, like smaller map, split
First/Last name fields and so on.

The current branch has been rebased to present a slightly idealised
picture of the process.)

(Includes contributions by @davea and @stevenday)

* Some code cleanup and added is_two_tier
* Add Hart-specific links to footer
* Shift FMS nav out of the main header
* Update styling to follow design more closely
* Flip nav colours to better indicate links
* Make header banner entire width of the page
* Stretch footer bg to entire width of page
* Add top-level nav links
* Correct header height on mobile
* Correct wording of top menu item
* Remove FMS logo from top of page
* Shift top level nav to correct position
* Invert media query so IE8 displays header properly
* hide folding triangle, as makes no sense on this cobrand
* Some more renaming of Bromley to Hart
* Treat Hart the same as Bromley in the JS
* Whitespace/formatting fixes
* Basic test for cobrand
* Javascript #map_box fixes
* Make sure #map_box is not in desk-only
* ensure there is only single map (one .wrapper only)
* colour tweaks
* Fix example places (postcode, spelling)
* Basic FAQ text
* Set Zoom level 3
* CSS/HTML/JS tweaks removing Bromley customizations
* Switch templates to put navigation in footer, as FMS.com does
* remaining HTML/CSS changes for large map
[Hart] move site-logo scss to one place
[Hart] header fixes
[Hart] fix jagged green box on mobile view

On mobile, the default brand doesn't have the box extend to the
"locate me automatically", so we use that same behaviour, setting
the hart primary box only on media query.
[Hart] fix recent photos box in Local Alerts
[Hart] footer work including social media icons
[Hart] fix alerts page width on desktop view
[Hart] make small logo transparent
[Hart] mobile header and images
[Hart] fixes restraining mobile view to max 100%

including hiding the footer on mobile view.
[Hart] fix display of logo on desktop
[Hart] footer and header fixes

with steve's help - fix header and footer on desktop and mobile
[Hart] message warns if problem sent to HCC

Should alleviate https://github.com/mysociety/FixMyStreet-Commercial/issues/481
However, note that if the user is already logged in, they won't be
stopped at this page.
[Hart] remove box shadow
Cobrand 'hidden_categories' method

This deals with the issue of hiding a two_tier category for the
Hart cobrand, without removing it for the whole of Hampshire,
e.g. see https://github.com/mysociety/FixMyStreet-Commercial/issues/477
but is written as a generic extension to setup_categories_and_bodies
as it may be generally useful.
[Hart] header and footer CSS tweaks

* white background colour on menu *wrapper*
    e.g. to have solid white menu bar for full width, not just the
    centered menu portion.
* 10em top-margin on map-page
* revert main nav font size
* Show menu items on mobile map-page
* Move the map-page menu item position:fixed into a media query
* Swap hart & fms nav on mobile
[Hart] favicon
[Hart] guidance re Hants on new report
[Hart] big green banner zindex reset

The banner goes above header, which looks odd, and Hart commented on
unfavourably.

As this happens in main FMS too, was unsure if it was deliberate,
but have confirmed with @dracos that is isn't.  This should be
fixed in main .scss, and can later be removed from Hart.

Same fix for z-index for "fixed" .banner
as per ysociety/FixMyStreet-Commercial#483 and #673
[Hart] updated wording re Hants

https://github.com/mysociety/FixMyStreet-Commercial/issues/485