Update README.md

README.md

 
 File access APIs were made when developing `v0.5.0`, which helping us write tests, and was not planned to be a part of this module. However we realized that, it's hard to find a great solution to manage cached files, every one who use this moudle may need these APIs for there cases.
 
-Before get started using file APIs we recommend read [Differences between File Source](https://github.com/wkh237/react-native-fetch-blob/wiki/File-System-Access-API#differences-between-file-source) first.
+Before start using file APIs, we recommend read [Differences between File Source](https://github.com/wkh237/react-native-fetch-blob/wiki/File-System-Access-API#differences-between-file-source) first.
 
 File Access APIs
 - [asset (0.6.2)](https://github.com/wkh237/react-native-fetch-blob/wiki/File-System-Access-API#assetfilenamestringstring)