add cpp serving for clas and pp-shitu

Dev/doc2

add tests of custom sampler;no eval; multicard eval

fix: upgrade replace_sub() to upgrade_sublayer()

add deephash config and model

supplement to PR #1581

fix bug caused by PR #1596

docs: update wechat qr code

1. remove WrapLayer and wrap_theseus;
2. support call update_res() one more;
3. optim parse_pattern_str() to return list of layer parsed.