Metaimageio

* Fix broken package.
* Reduce minimum required imageio version.

* Fix use of relative paths with .mha files.

See [individual commits](https://github.com/auneri/metaimageio/compare/v1.1.1...v1.1.2) for detailed changes.

See [individual commits](https://github.com/auneri/metaimageio/compare/v1.1.0...v1.1.1) for detailed changes.

* Skip unsupported field names when reading in MATLAB.

* Support for `ElementNumberOfChannels`.
* Support for non-ndarray input image to `write`.
* Fixed transposed orientations; applies to `Orientation`, `Rotation`, `TransformMatrix`.
* Dropped `ElementDataFile` from returned metadata to avoid accidental overwrites.
* Modernized conda environment configuration and CI.

Initial release!