Unmount buttons when corresponding screen is unmounted

Currently buttons were unmounted each time a screen was pushed to the stack.
As we're clearing props when screens are unmounted from the prop store - when a screen
was popped to - its buttons's props were undefined.

This commit changes things so that buttons are unmounted when buttons are set
using mergeOptions and when the corresponding screen is unmounted.

* Migrate to jest to support parallel ios simulator from detox

* When e2e lint only ts or js files

* Remove mocha from deps and decrease from 480000ms to 180000ms

* Make detox android test suit pass

Disabled emulator animations due to limitation of espresso/detox which can't wait until
a push/pop animation ends

* Fix orientation parsing and enable detox orientation tests

* remove only

* Fix BottomTabs testId

* Support user orientation

* Fix rightButtons testId

* Add Modals tests

* e2e fix ios

* largeTitleFix

* update to rn 49 - reload still not working on ios

* bridge fix

* small fixes

* testing with rn50

* removed package-lock

* go back to 49, problem with android in 50

* upgraded detox to version 6.x.x

* fixed detox script, added release config

This reverts commit c5a5382c0f.

This reverts commit 5e2a4d0878.