consider merging with firebase-mock

[soumak77]

I'm wondering whether you would like to merge this library with one I currently maintain: https://github.com/soumak77/firebase-mock. I'd be happy to help migrate any missing functionality that you need from this library.

[chetbox]

@soumak77 I want to apologise I hadn't seen this message until now. (3 years later!) It seems like Firebase testing, in particular with emulators, is better these days. Are you happy for me to close this issue?