Switch navigation to React Router about eeg-101

[jdpigeon]

Most of the routing is handled in index.android.js, so most changes should take place there.

We've also put our navigation into Redux in reducer.js

[jdpigeon]

Made new branch with React-Router work: https://github.com/NeuroTechX/eeg-101/tree/react-router

Seem to save about 20-50 mb at end of app with react-router. Transitions are unanimated but happen more quickly.

[jdpigeon]

Currently encountering some issues with the new react-router navigation: museDataListeners keep running after component is unmounted.

Will have to look and see whether this is a React or Java issue, or whether this is due to changes in the start/stop thread handling (which was happening before based on redux state keeping track of react-native-router-flux scene keys)

[jdpigeon]

Completed switch with commit 100! 6def8e4

Looks and feels better now, plus there's a little bit less memory used.

We lost the swipe animations and navbar. However, I'm not missing them.