Update steamkit, add more disconnect checks

Update SteamKit

Update SteamKit, ignore duplicate ChatEnterCallbacks

Remove use of deprecated SteamKit APIs, get rid of SteamClans since SteamKit now handles that

Update to latest SteamKit from NuGet, use C# 6

Don't wait for LoginKeyCallback to call OnConnected

Update SteamKit, make SteamPersona.PlayingName return null if not playing

Update dependencies

Add support for Steam Guard enabled accounts

Update SteamKit

Don't ignore multiple calls to SteamChat.Leave

Change a lot of names

Update libraries

Replace SteamGroupRank with SteamKit's enum

Missed a few