Use vendored fluxc and login

This PR introduces necessary changes to make the `assembleWasabiDebug` pass when using vendored `fluxc` and `login` modules.

Among others, this PR:
  - replaces coordinates of `fluxc` and `login` to point to local modules
  - updates dependencies and adds missing ones for vendored modules
  - unifies JVM version
  - adds necessary dependencies
  - fixes minor code issues, forced by Kotlin update on vendored codebase