* Add GC in train.py by defalut and change data co dataset in configs
* Update docs/INSTALL.md
* Enable build_strategy.enable_inplace = True

* test=develop add retinanet_r101 and delete needless configures in data feeder

* test=develop
add retinanet_r101 and delete needless configures in data feeder

* add VOC visualize

* fixn ssd_mobilenet_v1_voc.yml

* use default label

* clean TestFeed dataset config

* fix voc default label

* fix format

* fix as review

* revert voc default

* use defult label for all

* enable batch size != 1

* refine infer with args

* remove samples

* fix as review

* refine code

* refine args

* move get_test_images to infer.py

* add visualize log

* fix images = []

* fix args

* refine infer.py

* fix yolov3_r34.yml

* Unified object detection framework based on PaddlePaddle.
* Include algo: Faster, Mask, FPN, Cascade, RetinaNet, Yolo v3, SSD.