Clarify JavaScript module naming edge case
Clarify JavaScript module naming edge case

Summary:
I've been burned by https://stackoverflow.com/questions/35052565/undefined-is-not-an-object-from-native-module-in-react-native/36580178 a few times, when I name a native module with RCT prefix. This will hopefully save me and others from that pain in the future.

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Closes https://github.com/facebook/react-native/pull/14903

Differential Revision: D5390343

Pulled By: hramos

fbshipit-source-id: 73667d703b097e70e15ff42c54b7ccc6b480104f

pandiaraj44/react-native,hammerandchisel/react-native,janicduplessis/react-native,myntra/react-native,doochik/react-native,hoangpham95/react-native,makadaw/react-native,farazs/react-native,hammerandchisel/react-native,rickbeerendonk/react-native,javache/react-native,exponent/react-native,facebook/react-native,jevakallio/react-native,rickbeerendonk/react-native,exponentjs/react-native,farazs/react-native,ptmt/react-native-macos,pandiaraj44/react-native,exponentjs/react-native,janicduplessis/react-native,facebook/react-native,kesha-antonov/react-native,doochik/react-native,pandiaraj44/react-native,frantic/react-native,ptmt/react-native-macos,cdlewis/react-native,doochik/react-native,ptmt/react-native-macos,formatlos/react-native,janicduplessis/react-native,doochik/react-native,jevakallio/react-native,javache/react-native,negativetwelve/react-native,exponentjs/react-native,farazs/react-native,cdlewis/react-native,exponent/react-native,jevakallio/react-native,kesha-antonov/react-native,Bhullnatik/react-native,kesha-antonov/react-native,myntra/react-native,negativetwelve/react-native,farazs/react-native,Bhullnatik/react-native,pandiaraj44/react-native,facebook/react-native,javache/react-native,exponent/react-native,makadaw/react-native,myntra/react-native,hammerandchisel/react-native,makadaw/react-native,hoangpham95/react-native,hoangpham95/react-native,pandiaraj44/react-native,exponentjs/react-native,hoastoolshop/react-native,doochik/react-native,dikaiosune/react-native,javache/react-native,facebook/react-native,ptmt/react-native-macos,dikaiosune/react-native,hammerandchisel/react-native,rickbeerendonk/react-native,hoastoolshop/react-native,rickbeerendonk/react-native,farazs/react-native,janicduplessis/react-native,dikaiosune/react-native,kesha-antonov/react-native,Bhullnatik/react-native,pandiaraj44/react-native,javache/react-native,Bhullnatik/react-native,facebook/react-native,hammerandchisel/react-native,exponent/react-native,hoastoolshop/react-native,hoangpham95/react-native,hoangpham95/react-native,jevakallio/react-native,arthuralee/react-native,formatlos/react-native,myntra/react-native,kesha-antonov/react-native,janicduplessis/react-native,janicduplessis/react-native,Bhullnatik/react-native,rickbeerendonk/react-native,makadaw/react-native,hoastoolshop/react-native,farazs/react-native,farazs/react-native,formatlos/react-native,dikaiosune/react-native,hoangpham95/react-native,arthuralee/react-native,cdlewis/react-native,kesha-antonov/react-native,Bhullnatik/react-native,rickbeerendonk/react-native,negativetwelve/react-native,makadaw/react-native,negativetwelve/react-native,kesha-antonov/react-native,facebook/react-native,formatlos/react-native,negativetwelve/react-native,facebook/react-native,frantic/react-native,doochik/react-native,makadaw/react-native,exponent/react-native,hammerandchisel/react-native,jevakallio/react-native,doochik/react-native,hoangpham95/react-native,cdlewis/react-native,kesha-antonov/react-native,formatlos/react-native,jevakallio/react-native,jevakallio/react-native,javache/react-native,arthuralee/react-native,javache/react-native,negativetwelve/react-native,farazs/react-native,formatlos/react-native,negativetwelve/react-native,hoastoolshop/react-native,cdlewis/react-native,jevakallio/react-native,doochik/react-native,javache/react-native,myntra/react-native,dikaiosune/react-native,myntra/react-native,hammerandchisel/react-native,negativetwelve/react-native,exponent/react-native,exponent/react-native,arthuralee/react-native,ptmt/react-native-macos,janicduplessis/react-native,hoastoolshop/react-native,makadaw/react-native,janicduplessis/react-native,makadaw/react-native,frantic/react-native,frantic/react-native,exponentjs/react-native,hammerandchisel/react-native,javache/react-native,myntra/react-native,hoastoolshop/react-native,facebook/react-native,frantic/react-native,dikaiosune/react-native,ptmt/react-native-macos,jevakallio/react-native,dikaiosune/react-native,exponentjs/react-native,exponent/react-native,myntra/react-native,kesha-antonov/react-native,exponentjs/react-native,cdlewis/react-native,rickbeerendonk/react-native,Bhullnatik/react-native,ptmt/react-native-macos,formatlos/react-native,pandiaraj44/react-native,arthuralee/react-native,cdlewis/react-native,dikaiosune/react-native,hoangpham95/react-native,farazs/react-native,ptmt/react-native-macos,cdlewis/react-native,pandiaraj44/react-native,formatlos/react-native,rickbeerendonk/react-native,myntra/react-native,formatlos/react-native,hoastoolshop/react-native,Bhullnatik/react-native,doochik/react-native,facebook/react-native,exponentjs/react-native,makadaw/react-native,rickbeerendonk/react-native,cdlewis/react-native,negativetwelve/react-native