Watermelondb: Improve Documentation

[Batuu13]

Hey guys,

I've been having a hard time implementing stuff from the documentation. Most of the documentation gives a brief look at what is available but there is no detailed documentation. Even a simple relation is missing. We have post-author-comment example with missing schemas, missing models ( I mean fully, not partially because this is not working). I would love to contribute but first I need to learn how this works. All of the examples are using "_id" for relations but we don't know if this means the original "id" column or it is a self-generated custom "_id" column. I think documentation is super important for the newcomers if you guys want this project to grow!

I hope my positive criticism efforts won't get unnoticed, thank you!

[Unforgiven-wanda]

This one criticism is my one and only reason why I haven't yet used WatermelonDB in any project so far, even though I'd like to. I imagine myself getting stuck on a common-use case 2 days in and sifting through the issues and I just can't, not when there are other projects with proper docs and comprehensive examples.
tl;dr: The docs are beyond anemic, please do something about it.