[Breaking[ Modal refactor

* [Breaking] Showing modal removes the previously visible ViewController from hierarchy
* Modal implementation does not rely on Dialog
* Modal view is added to `content` layout
* Overlay is added to `root` layout, on top of the application's content
* Introduce StackControllerBuilder
* Show modal with animation
* Dismiss modal with animation
* Add previous modal at index 0
* Add root at index 0
* dismissAllModals dismisses only top modal with animation

This reverts commit a9b9d8379c.

Test Jenkins

Motivation:
When searching for the button's concrete TextView by label, if the
title has the same text as the buttons, both views are returned.

* Migrate to react v16.3 lifecycle & Add backward compatibility for older React versions

* remove yarn.lock

* migrate js and java to mergeOptions

* migrate ios to mergeOptions

This was occuring if a title has no properties set initially, but then are configured later. The title image data would go from [NSNull null] to nil, breaking this check.

By comparing against both values, we can ensure the correct logic for all behaviors.

* Rename to onChildWillAppear

* update roadmap

on clicking the outside of the sideMenu area sideMenu not closing,
because there is a problem in the code which i modified now

Each animation (push, pop etc) can be enabled or disabled separately

To save new RNN users some trouble, I've updated the recommended Obj-C that the installation guide tells us to paste over our App Delegate. I think the old one is obsolete because the #import and one of the Obj-C methods has change. Also removed a potentially misleading warning that might now cause users to wrongly blame their NPM version for trouble instead of these new changes. Anyway this new version works for me though someone might want to double check.

Removed reference to - (BOOL)application:(UIApplication *)application... The way it's worded makes it seem like you only need to overwrite what's in the function, not the entire file's code.

I made the text a little more punchy and easy to read.