Default shared/anonymous configuration to download app without giving auth details

[emanuelb]

Currently using this tool require to supply email&password&androidid for google account, this issue is about avoiding it by supporting Anonymous mode that use shared account, see for example other projects that implement this:
gplaycli: https://github.com/matlink/gplaycli

By default, gplaycli fetches a token from a token dispenser server located at https://matlink.fr/token/ to login in Google Play.

AuroraStore app: https://gitlab.com/AuroraOSS/AuroraStore

Anonymous accounts — You can log in and download with anonymous accounts so you don't have to use your own account

YalpStore app: https://github.com/yeriomin/YalpStore

By default Yalp Store connects to Google services using a built-in account, so you do not have to own a Google account to use it