Examples with Room: LiveData, Flow and RxJava (Observable, Flowable)

[RoarGronmo]

Theese are 3 (maybe four) different ways of implementing the 'flowness' of data in a pager scenario. Could you please split this codelab in 3 (4) different ways of implementing the paging and tell us the benefits drawback with each of them.

[florina-muntenescu]

Our docs contain examples of how to use RxJava and Guava/LiveData.
Adding all of this to the codelab would massively increase the codelab code and text maintenance burden.