* util/packagequery.py: it's used to query a RPM or DEB package. It also contains a
base class for all package types (PackageQuery())
* util/debquery.py: query a DEB package (name, version, release, provides, requires etc.)
- adapted util/rpmquery.py to use PackageQuery() as a base class
- minor changes in util/ar.py
* so far it was only used for querying rpms which can be done with the rpmquery module
- core.py:
* removed data_from_rpm() and tag_to_rpmpy() methods
- util/rpmquery.py:
* added staticmethod "query()"
- commandline.py, fetch.py:
* use rpmquery module instead of rpm-python/data_from_rpm()
