Summary:
Explain the **motivation** for making this change. What existing problem does the pull request solve?
The Android permissions native module was open sourced recently (https://github.com/facebook/react-native/commit/b7352b46671d09471d6aa9355ea41368ea05df96) but it is currently undocumented and requires directly interfacing with the native module.
This provides a JS wrapper to make it easier to use the permissions module and documents it.
This could be cleaner if the native code used Promise blocks instead of callbacks, but I didn't want to change the native code without a thumbs up since I'm guessing this is used in one of facebook's apps. Happy to do that if it makes sense
I also tried to make the `PERMISSIONS` object a class property - it works in the actual code but not in the documentation (think it's a jsdocs problem), so decided to initialize in the constructor.
**Test plan (required)**
If the API looks good, I will change the UIExplorer example to use this.
cc andreicoman11
Closes https://github.com/facebook/react-native/pull/9292
Differential Revision: D3716303
Pulled By: andreicoman11
fbshipit-source-id: cd40b8757fdf70ea8faecfb58caa00e99a99789e
Summary: Move all JS to a js/ subfolder so we get some overview of this folder again.
Reviewed By: bestander
Differential Revision: D3542598
fbshipit-source-id: 7637133fe4152f4d39e461b443b38510272d5bc8