Updated Visual studio project.

This commit fixes all warnings and errors due to changes made in code
blocks ubuntu. Everything compiles nicly!
The compiler setting in Code block is set to "-Wall".
I.e. Enables a lot of warnings. And some of the warnings was fixed in this commit.
Network protocol for start block changed.
Start block for the player is assumed to be sent in ascending player id order.
I.e. The player id are not sent as a part of the data packet.
Button should now always recognizing if the mouse is outside the window.
Merge branch 'newgui' of github.com:mwthinker/Tetris into newgui

Testing git.