Using the library without overriding onActivityResult

[jakubvimn]

Currently the client of the library needs to override onActivityResult in an Activity/Fragment. But it's possible to create a cleaner API without this requirement. Have a look at the Dexter library https://github.com/Karumi/Dexter for handling runtime permissions. The Android flow for permissions check also requires handling an external result, but the library hides that from a user. The trick is to start an Invisible activity that handles the result and delivers it to the library user. What do you think about implementing a similar flow for RxIAPv3?