Fix connections to asset-manager in development.

With the changes to gds-sso in #68, the dummy mode bearer token auth
only works if a token is given (it doesn't matter what it is, only that
one is sent).
Merge pull request #69 from alphagov/fix_asset_manager_in_dev

Fix connections to asset-manager in development.
Get rid of deprecation warning
Diambiguate selector in spec

This was failing when run locally.
Bump gds-api-adapters gem

Mainly to get at the newer panopticon test helpers, but also because it
was painfully out of date.
Bump plek gem
Bump rails point release
Bump formtastic gem
Don't require 'rspec/autorun'

This is no longer necessary and causes strangeness when running tests
with things like rake and zeus
Merge pull request #70 from alphagov/housekeeping

Update outdated gems
Add a diff view with previous edition

Currently just shows the diff of the main summary and the body of each
of the parts.
Tidy up markup on edit page
Make version history consistent with publisher

Mainstream publisher hides all but the most recent version history. This
makes travel advice publisher consistent with that.
parameterise CSS colours
Merge pull request #71 from alphagov/compare-editions

See diff with previous editions