feat: can use escaped tokens inside quotes including quotes. Change tokenizer to support: cmd with arg "string with embedded \" double quote" works for single quotes too. Mixed quotes can skip the \" or \' escaping. Also: quoted cmds args "can include \n newline, \t tab and \r return" Added a doc example, also tests for new feature.

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)