Added passphrase generated screen.
Passphrase is a 12-word mnemonic in this case and it is generated with bip39 lib.
It can be copied to clipboard or downloaded as a .txt file.
Change-Id: I031f6c0e92f4f783c07a2d8d35c0433c1d9a81ff
Shown only for free tier users.
Only appears at > 80% used storage or bandwidth (or both)
Different banner and modal styles for 100% used
Added resizable listener for banner
Change-Id: I29ac1777127155dab83b4eb113a1f033ea926524