* add stylegan2 and pixel2style2pixel models, predictors and documents

bug fix

* fix some bug

* add esrgan model, refine codes

* Integrate with visualdl
* visualdl: add doc and control paramter
* visual dl: move import, add install doc

* set en readme as default

* set en readme as default

* Add MidDaSv2 in ppgan.apps
* remove ppgan/apps/midas/run.py

* Update README
* Remove ppgan/faceutils/dlibutils/lms.dat
* Update apps.md

* add some custom gan models

* Add AnimeGANv2 in link

* Update README_en.md

* add animeganv2 network and dataset
* animegan:refine code,add License
Co-authored-by: Nqingqing01 <dangqingqing@baidu.com>

* Add Wav2Lip generator.

* fix auto downloading problem of dlib weight and add s3fd face detector

* Update README.md

* Update README_en.md

* add ugatit model

* fix import and docs

* docs: update install instruction

1. paddlepaddle2.0.0rc instruction can be found from main page
2. only two steps, install paddlepaddle and paddlegan, other than 3step

* docs: update en install
* feat: add dcgan
* reform: debug with mnist datset
validate performance with different options, and original structure and setting

* fix docs

* refine codes docs

* fix pix2pix to_tensor

* fix apps

* update setup.py

* refine duplicate frames and fix some bugs

* update readme

* add app apis

* add face_parse predictor in apps

* remove duplicate frames and keep timestamp, fix psgan docs

* update Readme