RainbruRPG's client is now in src/

Like this previous post, today's commit #826 is also on code reorganization.

This time, the client binary code was moved from the client/ subdirectory to the new src/ development tree.

This change includes C++ source code and  Ogre3D configuration files templates ( files) , used  by cmake to generate plugins.cfg and resources.cfg. The m4-based autotools  files were deleted while the remaining files, including TODO and ChangeLog, were moved to the OLD/client directory.

To make the whole project consistent, the last to-be-moved directory is services/.