Handle more ResourceWarning issues. admin.py - remove unneeded close. mailer.py - close debug log file. indexer.py - close read of version file memorydb.py - close python files being compled. Similiar to instance. not sure why it's compoing things and not just letting instance do it. .travis.ymv disable all except 3.9-dev till we get a handle on errors. also increase errors to 50 from 20.

def init_severity(db, cl, nodeid, newvalues):
    """Make sure severity is set on new issues"""
    if 'severity' in newvalues and newvalues['severity']:
        return

    normal = db.severity.lookup('normal')
    newvalues['severity'] = normal

def init(db):
    db.issue.audit('create', init_severity)