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.

* Migrate project to workspace

This commit moves all unit tests to the playground workspace

* Fix ios unit tests

* Build pods before testing

* Build typescript before running iOS tests

* Remove xcode 10 support

Break all the PRs :(

iOS and Android code base used different naming conventions - this commit aims to unify naming conventions. I probably missed a few properties here and there so this will be an ongoing effort.

* Enabled option was wrongly consumed after it was merged. That meant that the next time SideMenu options were applied, the wrong enabled value was applied
* supportedInterfaceOrientations didn't take default orientation value into account
* mergeOptions didn't save the new options in the ViewControllers current options
* SideMenu always returned the centre ViewController as the current child and didn't take open SideMenu into account

Fixes #5444

* Fix top bar layout frame, Closes #5003

* Set layout child view controllers on initialization

* Remove duplicate initWithLayoutInfo: function

* Explicitly attach and detach viewControllers in store
* Stop registering components in commands handler