* Run 'CHostState::Think()' in the main thread.
* Construct 'NetGameServer_t' objects in main thread before dispatching (TODO: browser).
* Dispatch the call to 'CBanSystem::AddConnectionRefuse' from 'SV_IsClientBanned' to the main thread if we aren't main.
* Return bool for CBanSystem::AddEntry and CBanSystem::DeleteEntry for future optimizations (next commit).
* Only run '_DownloadPlaylists_f()' in the main thread, schedule for next frame if we aren't in the main thread. (this should fix crash cases related to disconnecting from the game).
* Locked read/write to CBrowser members (thread for obtaining the server list is detached, but once the 'slow' post operation in this thread is complete, mutex lock is acquired (locking the render thread if the browser is active) to set the string members of CBrowser, this operation is very fast as we only set the string and the color after the http post operation (this never caused a crash, but the behavior without any lock mechanism is technically undefined regardless).
* Obtain the host name dynamically from the ConVar 'pylon_matchmaking_hostname' (atomic operation). Initial approach was deleting the whole master server pointer just to construct a new httpclient object..
Run all Cbuf_Execute calls in the main thread. This should fix every problem related to (but not only):
* Connecting to server while RUI dialogue is still open.
* Connecting to server while in an active game.
* Running 'weapon_reparse'.
