Replace splash screen library

[isaiahgrey93]

Recommend we use https://github.com/zoontek/react-native-bootsplash for managing the splash screen state. The react-native-splash-screen package has always had an issue on IOS where you weren't able to re-show the splash screen after the initial display. However, react-native-bootsplash allows you to display/hide whenever, and also solves some layout issues causes by showing/hiding by actually rendering this view inside the root view instead of replacing it. Another cool thing is animation in/out of the splash screen is configurable through SplashScreen.show({ duration: 1000 }) or SplashScreen.hide({ duration: 1000 })

[code-jenn-or]

I have removed react-native-splash-screen in the Upgrade PR #161 because iOS release build no longer functioned with the out of date library. The .storyboard files do need to be updated but are included in this change.

So we should close this issue and open a new one to update the new storyboard file.