Check TFT app version and exit if it's outdated

[akshualy]

Changes:

• Adds the python package google-play-scraper to the dependencies
• Uses google-play-scraper to get the latest TFT app version from Google Play
• Uses adb to get the current TFT app version
• Compares the versions, and if the Google Play version is newer than the current one, exits with a message to update (and why to update)
• Makes tft_package_name public, so we can access it more easily - Should probably have some globals/constants somewhere eventually
• Adds more debug lines to which precondition we're checking, to determine if we get stuck on some step
• Removes the TODO of updating via APKMirror, it's simply not worth the effort

[Detergent13]

Looks good to me!