Add Android dot files to .gitignore (#27589)
Add Android dot files to .gitignore (#27589)

Summary:
Added dot files to `.gitignore` these got generated opening the project in Android Studio or running Gradle scripts.

<img width="570" alt="Screen Shot 2019-12-21 at 4 05 36 PM" src="https://user-images.githubusercontent.com/8675043/71315203-48ee3680-240c-11ea-9600-218e11b194b5.png">

## Changelog

[Internal] [Added] - Added Android Studio dot files to gitignore
Pull Request resolved: https://github.com/facebook/react-native/pull/27589

Differential Revision: D19235583

Pulled By: cpojer

fbshipit-source-id: eb265d516e125aeb64807efe42832b80d7977b18

facebook/react-native,pandiaraj44/react-native,hoangpham95/react-native,facebook/react-native,exponent/react-native,myntra/react-native,exponent/react-native,myntra/react-native,exponent/react-native,janicduplessis/react-native,myntra/react-native,arthuralee/react-native,javache/react-native,facebook/react-native,hammerandchisel/react-native,hammerandchisel/react-native,exponentjs/react-native,hoangpham95/react-native,javache/react-native,facebook/react-native,myntra/react-native,myntra/react-native,exponentjs/react-native,facebook/react-native,pandiaraj44/react-native,facebook/react-native,pandiaraj44/react-native,exponent/react-native,janicduplessis/react-native,hammerandchisel/react-native,janicduplessis/react-native,hammerandchisel/react-native,hoangpham95/react-native,hammerandchisel/react-native,javache/react-native,pandiaraj44/react-native,facebook/react-native,exponentjs/react-native,myntra/react-native,exponentjs/react-native,javache/react-native,pandiaraj44/react-native,myntra/react-native,hoangpham95/react-native,exponentjs/react-native,arthuralee/react-native,exponent/react-native,pandiaraj44/react-native,janicduplessis/react-native,hoangpham95/react-native,pandiaraj44/react-native,facebook/react-native,myntra/react-native,hoangpham95/react-native,myntra/react-native,janicduplessis/react-native,javache/react-native,hoangpham95/react-native,javache/react-native,arthuralee/react-native,javache/react-native,exponent/react-native,hammerandchisel/react-native,exponentjs/react-native,exponent/react-native,arthuralee/react-native,janicduplessis/react-native,janicduplessis/react-native,javache/react-native,hammerandchisel/react-native,pandiaraj44/react-native,exponent/react-native,janicduplessis/react-native,arthuralee/react-native,exponentjs/react-native,hoangpham95/react-native,facebook/react-native,exponentjs/react-native,javache/react-native,hammerandchisel/react-native