add an optional content disposition mode, so you can use inline if needed
Bug fix, to use new gridfs
Revert "Bug fix, to use new gridfs"

This reverts commit 05a8e2cc88434ae912c9e5250fa37a6ac232dee8.
Merge commit '9dff48ab4e9a9c1be04a20181832b6de218091e1'
real bug fix, also test with reactivemongo-demo-app
Merge pull request #24 from jkyamog/master

add optional content disposition mode parameter, this way we an either use attachment or inline download