0.9.0

What's Changed

• Optionally configure Firefox location using FIREFOX_BIN
  environment variable. Thanks, @gogglespisano and @intermittentnrg.
• Added CLI options --window-size and --zoom-factor.
  Thanks, @intermittentnrg.
• Fixed login by waiting a little. Thanks, @maurerle.

Full Changelog: 0.8.1...0.9.0