Added i18n configuration of homepage.
Added i18n configuration of homepage.

This adds a local copy of the translation.json file that contains
headline, subhead, and call-to-action translations for the
homepage. This requires PR 18F/midas#348 to have been applied.

Fixes #8

18F/open-opportunities-theme,18F/open-opportunities-theme,18F/midas-open-opportunities,18F/midas-open-opportunities