Some concurrency fixes

I've hopefully resolved the back-end issue stopping new accounts actually being created in the database - you should now be able to change your name/add friends etc.

Added a reset password button because someone always forgets their password.

Tiles should now "lock" in your client when you perform an action until that action has been completed. This should mean you're no longer able to attempt numerous actions at the same time .

The Debug menu(available via F2) will now show you a version date.

Only the host of a lobby should be able to click the 'Start Game' button.

Units now switch between their normal rendering type and a ship when they are embarked.