deposit: plupload improvements

* Allows autoupload on file selected.

* Fixes a bug when deleting a file right after uploading it.

* Fix in Blueprint url endpoints for upload urls.

Signed-off-by: Javier Martin Montull <javier.martin.montull@cern.ch>
sqlalchemy: addition of Encrypted type

* Adds a custom type which is called `Encrypted`. It uses
  the AES algorithm provided by pycrypto in order to encrypt and
  decrypt.

Signed-off-by: Konstantinos Kostis <konstantinos.kostis@cern.ch>
sqlalchemy: fix default integer constructor

* Addresses issue with default constructor on types that do not
  accept arguments in SQLAlchemy>=0.7. (closes #1776)

Signed-off-by: Leonardo Rossi <leonardo.r@cern.ch>
WIP deposit: new uploader component

* Adds Uploader - flight component for handling all different uploaders

* Adds PlUploader

* Adds DropboxUploader

Signed-off-by: Adrian Pawel Baran <adrian.pawel.baran@cern.ch>