deposit: js uploader component

• Adds flightjs uploader component with support for pluggable uploader engines such as PLUpload and DropBox.

• NOTE RequireJS path to FlightJS was changed from vendors/flight/lib to vendors/flight. Scripts defining flight components MUST update their require statement from require('flight/lib/component') to require('flight/component').

Reviewed-by: Lars Holm Nielsen <lars.holm.nielsen@cern.ch>
Signed-off-by: Adrian Pawel Baran <adrian.pawel.baran@cern.ch>