Sevket Yalcin 09189002c6 Fix typo on CRA's package name (#21219) ...

The create-react-app installation npm command has a typo: 
```npm install -g react-create-app```
Instead of 
```npm install -g create-react-app```

2018-10-20 22:56:54 +05:30

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index.md

Fix typo on CRA's package name (#21219)

2018-10-20 22:56:54 +05:30