Upload Dialog to integrate with SFTP

[Tat Seng Wong]

Currently the upload dialog is inherit from Canvas, problem is the files only able to upload to Canvas' installation folder, which is not ideal.

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If possible to integrate with SFTP, it would be much better, especially on a Cloud environment, we can point to different sftp directory for different upload requirement.

[Scott Wiltshire]

Removing milestone: 2020_Q4 (automated comment)