Updated CMakeLists for qhull-2012.1

[Brad Barber]

Hi all,
Petr Gajdos identified a problem with CMakeLists in the recent update to 
qhull-2012.1.  It is fixed on qhull.org and gitorious.org/qhull.

                        --Brad

Please let me know about any problems.
   http://www.qhull.org/news/
   
Qhull 2012.1 requires option 'Qz' for the Delaunay triangulation and Voronoi 
diagram of cocircular and cospherical sites (thanks to Damian Sheehy).

It cleans up the build as suggested by Marco Atzeri.
- Renamed libqhull6_p.so to libqhull_p.so.
- Moved Road*.h and Road*.cpp into libqhullcpp and qhulltest
- Removed cmake's target VERSION from executables
- Set cmake's SOVERSION to 6
- CMakeLists: Remove the installation of user_eg* and testqset
- Install to share/doc/qhull instead of share/doc/packages/qhull
- On Unix systems, install to share/man/man1 instead of man/man1

The following conventions were retained:
- The qhull executables use the static libraries instead of the shared 
libraries.   Static linkage simplifies configuration.  
- The debugging libraries are identified with a 'd' suffix (e.g., 
libqhull_d.so).  This allows a package to ship both release and debugging 
versions as selected by a symlink.
- The static libraries are named with 'static' (e.g., libqhullstatic.a).   This 
avoids naming conflicts with libqhull.dll.  While there appears to be 
workarounds, the workarounds were dependent on the build environment.  

Qhull needs a Debian/autotools build.  Ideally it would build all of the 
libraries.  I've drafted some changes for Rafael Laboissiere's Qhull 2009.1 (in 
the config/ directory).   I do not have an autotools environment to test these 
changes.

Qhull also needs an RPM distribution.  Please let me know about any builds to 
post on the Download page.

                                --Brad