Add iOS support for `bottomTabs.attachMode`.
This property controls when BottomTabs children are attached to hierarchy and when their React views are created.

By default, RNN attaches all children at the same time which might impact loading time as a few screens are instantiated at once.
Using `afterInitialTab` or `onSwitchToTab` generally leads to improved start up time.

* Layout changes

* WIP

* Revert "Layout changes"

This reverts commit 4da8cfbd12.

* Clean topBar.component and topBar.background.component when not needed

* Move custom components login from viewController to presenters

* Change waitForRender and enabled property from primitive bool to Bool object

* Fix ios unit tests

* Add unit tests

* Remove RNNReactView observer when view ready

* Load react components from component manager

* Remove createCustomReactView duplication

* Handle render children in each Layout

* Wait for navigation presenter components render, refactor RNNTitleViewHelper

* Fix unit tests

* Add waitForRender for custom react components

* Fixes e2e

* bind viewController to presenters using bindViewController

* Merge options to the specific provided layout

* Moved custom titleView creation to RNNRootViewController

* Moved default options to presenters, moved options applying to presenters, resolved options in RNNOptionsResolver

* Fixes merge options

* Fixes topBar transition on pop

* Prevent titleView creation when react titleView exists

* Fixed unit tests

* Options refactor WIP

* Detach applied options from DTO - WIP

* Added option types and option parsers

* Unit test passes

* Added presenters for each parent type

* Fixes unit tests

* Rename StringParam to Text, changed bottomTabs.drawBehind and topBar.drawBehind default to false

* set layout.backgroundColor default to white

* Added unit tests for RNNViewControllerPresenter

* Set layout.backgroundColor default nil

* Fixes buttons color missing options

* Fix unit test

* fix button color parsing

* Moved default options to presenters

* default options fixes

* Fixes e2e

* Fixes unit tests

* Resolve child options on childWillAppear

* Recrusively setDefaultOptions on rootViewController tree

* Fixes default values

* Fixes tests

* fix custom header

* fix e2e

* pass props for topBar background component

* refactored custom components

* pass props for topBar background component

* refactored custom components

* refactored RNNOptions object

* Use margin to control component position relative to TopBar

RelativeLayout rules caused excessive CPU usage due to issues with RN's
keyboard detection mechanism (based on global layout listener)

* Skip custom transition e2e on Android

* Improved the clarity of the top-level API doc (#2984)

I clarified some of the language here so that it is easier for the beginner to understand. (It was a little bit awkward before)

* Increase gradle daemon process memory

* Disable Orientation test on Android

* Fix SideMenu e2e

* Fix popTo

* Use margin instead of RelativeLayout rules to align component to BottomTabs

Rules caused excessive CPU usage due to RN issue with global layout listener
and keyboard visibility detection.

* Update README.md

for triggering build

* Update README.md

* Consolidate pop and animatePop

* Update top-level-api.md ... more copyediting. (#3002)

Further clarification of some of the top level API stuff.

* popTo animates top screen

* Refactor component options on Android

* Stop processing passProps from options

* removed comments

* changed this.props.id to this.props.containerId

* fixed js tests

* refactor