Partial code cleanup for dead code

controllers/data_controller/import_controller.go

controllers/download_controller/download_controller.go

controllers/download_controller/download_resource_handler.go

...rollers/maintenance_controller/maintainance_controller.go

controllers/quarantine_controller/quarantine_controller.go

controllers/upload_controller/upload_controller.go

internal_cache/LEGACY.txt

internal_cache/cache.go

internal_cache/instance.go

internal_cache/noop.go

internal_cache/redis.go

internal_cache/streamer.go

matrix/admin.go

matrix/responses.go

pipelines/_steps/download/try_download.go

storage/storage.go

util/stream_util/streams.go