Documenting compute capabilities. Renaming query.py to swarm-query.py in the documentation.
Fix TutorialPython linking issue, fix some formatting issues in util.cpp.
Documenting range_type.py and libswarmng_ext: the C++ to Python bridge

* There are some changes in naming that are transparent to user: Sys, SystemRef -> System
* The documentation is put into __init__.doc.py, the file is never executed by Python but
it is included in the documentation.
* Everything that is defined in module.cpp is documented in __init__.doc.py.