better engine.url.translate_connect_args() and related

[Former user]

engine.url. * def translate_connect_args(self, names): this assumes the order of passed names matches the order of attribute_names inside... very fragile. i suggest using set of kwargs like (attr_name=replacement_name), then just use the non empty ones. Fixed also several usage-related omissions.

• def _parse_rfc1738_args(): the 'opts' dict is redundant, args can be just passed to URL( name=value)

[Former user]

check if doc comment on the func makes sense

[jek]

83d05aa5aff0b27027fb10986390d898a3153eb2