billiard: Delete too old or multibyte-containing commented codes

We wouldn't revive codes that have been killed five years ago and never
be demanded again!  If we would really miss them, we could restore them
from the history at any time.
billiard: Delete project file for old Visual Studio

The project file and the solution file are placed in a directory named
Monster, which was name of a computer.  This naming convention does not
cope with open source distributedly version controlled project, hence
deleted.

Now that we have VC2012 project files in another directory, we really
do not need older versions of the project files.
billiard: Delete more obsolete project file

There's a prject file for VC2003, which was too ancient to exist at all.
billiard: Quit smoothing camera chasing the ball

Previously, the camera position is smoothly interpolated, but in reality
what we need to smooth is the distance of the camera and the focus.

This change will eliminate 'laggy' feeling of the camera while
preserving smooth zoom interpolation.