Support for setting 'Cache-Control' header on uploads.
Ensure we also copy the other 'http header metadata' when getting the key metadata.
ValidateS3UploadForm now 'processes' uploads. Uploads are now stored in a separate location before/after processing.
Removed unused import.
Added change log to docs.
Version bump.
Merge branch 'development'
Renamed ``get_processed_content_type`` to ``get_upload_content_type``.
Dropzone styling - only apply success class after file has been processed - and trigger error if process fails. jslint cleanup.
Support for custom processed_key_generator functions.
CSRF validation for redirect 'GET' requests which cause processing of upload.
Version bump.
Merge branch 'development'