Remapping input and clicking on text fields soft-lock the game

[JayFoxRox]

This is because the wndproc is not implemented. The function should be kept when CreateClass is called and then the message loop should be handled properly.

I'm not sure how the game maps DirectInput scancodes (keycodes?) to Win32 scancodes (keycodes?).
So this might need some special attention (such as synchronizing DirectInput and wndproc events).

A temporary workaround is to implement #36 and keep the default profile / mapping.

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A similar thing happens when leaving the current multiplayer session, but that might be unrelated. Also master has no multiplayer support yet, so that is beyond the scope of this issue.