Release v0.2.1

Release 0.2.0 (qubvel-org#430)

* new in_channels != 3 initialization
* docs fixes 
* version resolving

Fix typehints, improve error raising for encoders

Fix pytorch-efficientnet version (qubvel-org#264)

* Update requirements.txt
* Update __version__.py

Release v0.1.1 (qubvel-org#263)

* Update README.md

* Update __version__.py

* Update README.md

fix SCEModule.sSE (qubvel-org#113)

Update __version__.py

Fix content type

Merge branch 'docstrings'