Set correct mime type when uploading to S3.
Set correct mime type when uploading to S3.

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sferik/rubinius,ngpestelos/rubinius,kachick/rubinius,kachick/rubinius,jsyeo/rubinius,jsyeo/rubinius,jsyeo/rubinius,sferik/rubinius,ngpestelos/rubinius,sferik/rubinius,ngpestelos/rubinius,ngpestelos/rubinius,kachick/rubinius,sferik/rubinius,kachick/rubinius,jsyeo/rubinius,sferik/rubinius,kachick/rubinius,sferik/rubinius,kachick/rubinius,jsyeo/rubinius,kachick/rubinius,ngpestelos/rubinius,jsyeo/rubinius,sferik/rubinius,ngpestelos/rubinius,jsyeo/rubinius,ngpestelos/rubinius,kachick/rubinius