Add odidown gem
update odidown version
ignore config
load dotenv before bundler.require to fix Plek
Attach news item images
Don't require virus scan in order to display.

Temporary fix, pending resolution of theodi/asset-manager#3
pull in embed changes from odidown
Generalise URLs stubbed in tests
Load configuration manually at start of tests

but turn off asset-manager basic auth as far as tests are concerned
Fix asset manager paths for stubs
Include NewsEdition video
Attachment fields aren't needed in RABL