more cleaning of files created during tests
coverage.py: ingore override class methods
testing: ignore modules importer.py ocli.py

these modules are legacy code which is not tested
and not used. They should be removed in the next
pwman3 release
fix broken testing for config.py
remove support for old <2.7 python versions

pwman3 start up script uses argparse, which coherces
python 2.7. Which in turn has built in SQLite support.
remove old sqlite driver class to it's own module

the code is not testable and is only there for conversion
support
add SQLiteDatabase import to sqlite.py

for backwards compatability
ignored old osqlite.py module

it is obsolete and not testable