Merge remote-tracking branch 'origin/travis/s3'

config.sample.yaml

src/github.com/turt2live/matrix-media-repo/api/r0/upload.go

...om/turt2live/matrix-media-repo/api/webserver/webserver.go

...ub.com/turt2live/matrix-media-repo/cmd/media_repo/main.go

...b.com/turt2live/matrix-media-repo/common/config/config.go

...thub.com/turt2live/matrix-media-repo/common/errorcodes.go

...po/controllers/download_controller/download_controller.go

...trollers/download_controller/download_resource_handler.go

...rollers/maintenance_controller/maintainance_controller.go

...repo/controllers/preview_controller/preview_controller.go

...ontrollers/preview_controller/preview_resource_handler.go

...ers/preview_controller/previewers/calculated_previewer.go

...ia-repo/controllers/preview_controller/previewers/util.go

.../controllers/thumbnail_controller/thumbnail_controller.go

...ollers/thumbnail_controller/thumbnail_resource_handler.go

...a-repo/controllers/upload_controller/upload_controller.go

...turt2live/matrix-media-repo/internal_cache/media_cache.go

...b.com/turt2live/matrix-media-repo/matrix/client_server.go

...thub.com/turt2live/matrix-media-repo/matrix/federation.go

...github.com/turt2live/matrix-media-repo/metrics/metrics.go