Exit animations support

[NiuGuohui]

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• I tested using the latest version of the library, as the bug might be already fixed.
• I tested using a supported version of react native.
• I checked for possible duplicate issues, with possible answers.

Bug summary

I saw in the documentation that this library also supports exit animations, but I couldn't find any instructions related to exit animations in the documentation. How can I implement this?

Library version

0.7.2

Environment info

.

Steps to reproduce

how?

Reproducible example repository

none