feature: Implement custom fade out duration

[TheNerdGuyLulu]

Summary

This feature implements a custom duration for the splash screen fade out.
The parameter is optional, with the default being 220ms, as it was already before, making it backwards compatible without any changes for the current consumers.

Test Plan

What's required for testing (prerequisites)?

Android emulator & iOS simulator is enough.

What are the steps to test it (after prerequisites)?

import {
  View,
} from "react-native";
import * as BootSplash from "react-native-bootsplash";


export const App = () => {

  React.useEffect(() => {
     BootSplash.hide({fade:true, duration: 2500}); // Edit duration
  }, []);

  return (
    <View />)
};

Compatibility

OS	Implemented
iOS	✅
Android	✅

Checklist

• I have tested this on a device and a simulator
• I added the documentation in README.md
• I added a sample use of the API in the example project (example/App.tsx)

The current example project isn't "visually" compatible with this feature, as the logo is hidden from JS.

[zoontek]

@TheNerdGuyLulu There's a small issue here (not in the PR, but in the feature).
I noticed that on Android, when the duration is short (ex: try 100ms), it just doesn't fade at all.

The feature might exists, but it needs to be clamp at 220 (native side equivalents of Math.max(220, userDurationValue) on both iOS and Android

[TheNerdGuyLulu]

@zoontek Thanks for such quick code review.
I'm going to take care about this comments ASAP.

[TheNerdGuyLulu]

The feature might exists, but it needs to be clamp at 220 (native side equivalents of Math.max(220, userDurationValue) on both iOS and Android

@zoontek Wouldn't be enough to use Math.max(220, userDurationValue) and send it from JS, instead of native function?
I'm happy to go with native way, just asking since a value is required to be given to the function (right now the 220 is default value from JS side) - we can do the math from JS.

[zoontek]

@TheNerdGuyLulu Yeah, close enough to do it on the JS side

[TheNerdGuyLulu]

@zoontek CR comments addressed 🤞🏻

[TheNerdGuyLulu]

@zoontek
Could you please take a look when you have the time? 🙏

[zoontek]

LGTM, thanks