Changed studiobar donate tile to /shop instead of /donate. New thumbnail.
Merge pull request #869 from code-dot-org/shop-thumbnail

Changed studiobar donate tile to /shop instead of /donate. New thumbnail.
added internationalized shop strings
Hoc Survey 2014 Prize Code Claiming
Added field definitions for survey form.
Dropbox and GSheet changes.
Merge branch 'staging' into test