Implement command autocomplete

[limoka]

With current free form command system autocomplete is essentially impossible, because parsing anything requires full command to be already present.
Only solution I came up with:

• Force command arguments to follow strict format.
• For any arguments with spaces introduce quotes (" or similar) to indicate beginning and end

This would entail the following approach

1. Parse arguments (On the client)
2. Preprocess any arguments that need it. For example (Command Localized names don't work when host is dedicated server #21)

At this point we also could use current parsed representation to provide autocomplete to users

3. Send command in parsed form
4. Execute the command