Implement enough of the functions to support the itch plugin

[AndrewDWhite]

The itch plugin also suffers from needing game updates while running, #18 , to be working correctly to enable at least the loading of the local data. It also needs the login functionality, at least #10 , to support loading all games from web api.

[AndrewDWhite]

Will have to look into how the plugin utilizes the next data as the following result is insufficient.
: msg: {"id":"4","jsonrpc":"2.0","method":"pass_login_credentials","params":{"cookies":null,"credentials":{"end_uri":"http://127.0.0.1:7157/gogg2itchintegration#access_token=TokenRemoved"},"step":null}}

[AndrewDWhite]

Look at the following code:
https://github.com/tauqua/gog-galaxy-itch.io/blob/master/src/itch.py#L47