Fix
* Replace `mktemp` with `mkstemp` when caching to disk for legacy plugins ([1055](https://github.com/imageio/imageio/issues/1055)) ([`12b1ad2`](https://github.com/imageio/imageio/commit/12b1ad24f9a613d42c282c6581207f6899ef7f45))
Other
* Fix grammar in ImportError ([1054](https://github.com/imageio/imageio/issues/1054)) ([`56cfd79`](https://github.com/imageio/imageio/commit/56cfd7905358d88e50ab43da6e864e13c88d2be5))