Add a game start dialog

[Henrik Heimbuerger]

After configuring the game in the player view, the user should be able to start a game using a toolbar button.

This should invoke a game start dialog that shows the game startup process in multiple phases. Depending on the game configuration, this might also require interaction with the user.

Which phases are required needs to be determined, but definitely comprises of:
1. Initialisation of input devices, for example Wiimotes have to be connected to the system if they haven't before.
2. Initialisation of the specific track controller, for example when using 42 for the first time (or maybe always?), the cars have to be given unique IDs.

3. Some kind of preparation phase, so all players are ready to start the race. This could f.e. be visualised with traffic lights.

[SVN]

New commit by frohn (revision [79]):
[Partial fix for ticket #14] First Skeleton of the RaceStart? dialog with a progress bar added.

[Henrik Heimbuerger]

Steps one and two are no longer necessary under the new design and have been crossed out.

The new expected behaviour of the game start dialog is:

1. Check if all players have a non-empty name and a selected car. Abort and report if not.
2. Check if all players have an input device that is connected (InputDeviceManager has to be asked for the ID). Abort and report if not.
3. Check if all players have a technology that is connected and configured (TechnologyConfigurationManager has to be asked for the ID). Abort and report if not.
4. Check if all technologies are compatible with the used track type (e.g. no BlueRider on digital tracks). Abort and report if not.
5. Switch the active perspective to the race perspective.
6. Show the staging lights, and wait until they are done.
7. Start the RaceEngine.