Initialize a Content API client on the Maslow module
Return artefacts from the content API for a need
Remove superfluous includes of API Adapter test helpers

The API Adapter test helper modules are included in
the integration_test_helper.rb file, so it is
unnecessary to require them again here.
Display a list of content which meets a need

This makes a request to the content API to return
a list of artefacts which meet the Need ID of the
current need.

For the time being, stub out all the requests
to the content API in the integration tests.
Bump gds-api-adapters to 7.21.0
Don't blow up when the Content API returns an error
Show a table of content which meets the need

- Show GOV.UK content which meets this need
- Add format column to help distinguish between need formats
Tweaks to the artefact table

Add an id attribute to the table, and use humanize instead of
capitalize on the artefact.format string.
Add integration test coverage for listing artefacts

Add integration tests to cover showing a table of artefacts for
a need from the Content API.

This stubs the requests to the Content API and also tests
behaviour when the Content API is unavailable or returns an error.
Use separate api client credentials for each API
Merge remote-tracking branch 'origin/master' into list-mainstream-content-for-need

Conflicts:
	Gemfile
	Gemfile.lock
Merge pull request #37 from alphagov/list-mainstream-content-for-need

List mainstream content for a need