For https://github.com/turt2live/matrix-media-repo/issues/457

The download pipeline returns a CancelCloser, making this required.

This reverts commit 9ee13765.

This reverts commit d3eb5a99.

For https://github.com/turt2live/matrix-media-repo/issues/445

For https://github.com/turt2live/matrix-media-repo/issues/450

For https://github.com/turt2live/matrix-media-repo/issues/415

For https://github.com/turt2live/matrix-media-repo/issues/413

For https://github.com/turt2live/matrix-media-repo/issues/413
For https://github.com/turt2live/matrix-media-repo/issues/409

For https://github.com/turt2live/matrix-media-repo/issues/407
For https://github.com/turt2live/matrix-media-repo/issues/408
For https://github.com/turt2live/matrix-media-repo/issues/409

This reverts commit 5e51abbd.

For https://github.com/turt2live/matrix-media-repo/issues/53

This is probably super ugly Go code, but it works.