Full-bleed photographs that can fill device width
Full-bleed photographs that can fill device width

Summary:
asana: https://app.asana.com/0/132409062806753/139320310169075

zeplin: https://zpl.io/Z1uDr7J

{F543707}
{F543708}
{F543709}
{F543710}

Test Plan:
- `make fastbuild`
- pass `xom_manatee_beta` gandalf bridge
- open chrome dev tools iphone5 emulation
- open perseus article with images ([example](/puppies/mobile-product/the-mobile-opportunity/a/navigation-google-maps))
- see full-bleed photographs, while images/diagrams are not full-bleed

Reviewers: charlie, benkomalo

Reviewed By: benkomalo

Subscribers: cameron, jared

Differential Revision: https://phabricator.khanacademy.org/D28168

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