Support for debian/ubuntu package generation metadata 

This pull request will bring support for build debian/ubuntu packages providing the metadata needed in debian/ directory. I tried to be at less intrusive as possible but end making a few changes in the code base. It is prepared to build on quantal but can easily adapted to other distributions.

Details:

* Implement soname in libraries: this will generate proper versions of libsimbody (and friends) in the form of libsimbody3.3. This is assuming that ABI will be stable during 3.3. It can be adjusted as needed.
* The foillowing packages will be generated:
 * libsimbody3.3: libraries  (stripped versions)
 * libsimbody3.3-dbg: debug symbols for libraries
 * libsimbody-dev: headers, cmake finder and symlink to libraries
 * libsimbody-doc: pdfs and api html

In the copyright file I've included all I've found, but some authors/licenses could be missing.