Update README.md

- Bumped target SDK to 30

- Handled scoped storage - setCopyImagesToPublicGalleryFolder should work again on devices running Android 10 or newer
- Fixed rotation of images when saving to public gallery

- Fixed bug with overriden module name

- Fixed bug with multiple images on documents
- Added EasyImageStateHandler to builder for saving state
- Updated gradle

Makes sure cleanup is done before starting another picker

Reintroduces library in kotlin.

It's not backward compatible, but new readme explains it all.
It became simplier and easier to maintain.