SteamFriends and SteamUser Changes

[Crytilis]

This PR would implement the following changes as listed on the commits;

• Added AdvertiseGame to SteamUser so that it may be used for clients.
• PersonaChange enum is now set to public rather than internal so it may used with the PersonaStateChange callback.
• Modified the PersonaStateChange callback for SteamFriends to include the PersonaStateChange_t flag as defined in the PersonaChange enum.
• Removed the F word from the readme in the event that prospective employers are looking at a forked GitHub.

[Crytilis]

Must have overlooked that, the correction has been made. I did make a few more changes some of which were for compilation testing.

• Updated Test Adaptor and Framework packages
• Updated Newtonsoft packages
• Modified the folder path to account for .NET6 changes as the compiler was throwing errors regarding path until the change was made.
• Set the steam_api.json file to copy to output upon compilation to prevent compile errors as it was throwing on it missing until this change was made.

[garrynewman]

There's a few too many unexplained changes here for me to pull this.