Remove all keys from the selected database

    CLI Example:

    .. code-block:: bash

        salt '*' redis.flushdb

def flushdb(host=None, port=None, db=None, password=None):
    '''
    Remove all keys from the selected database

    CLI Example:

    .. code-block:: bash

        salt '*' redis.flushdb
    '''
    server = _connect(host, port, db, password)
    return server.flushdb()