* add cascade mask

* add cascade rcnn

* update code

* remove comments

* split yolov3 loss using paddle op

* add sync_bn and modify list to LayerList to use sync_bn, add missing op, support cutmix op in dataset, modify reader to use new ops

* modify code according to review

* modify code to run eval.py successfully

* modify code to run eval and train successfully

* modify code to use mixup

* rebase code on lastest dygraph

* modify code to run in sync_bn mode

* modify code according to review

* modify target size of ResizeOp

* update mask_rcnn_fpn model

* update smooth_l1_loss

* update smooth_l1 and sigmoid_cross_entropy_with_logits

* fix relu name

* refactor dygraph & add mask rcnn fpn

* fix initialization & minor update

* refine architecture of mask_rcnn

add cascade rcnn and modify make net method
add new cfg method 
add auto debug tool

add yolov3

add faster rcnn\mask\cascade rcnn model arch\module\op
add base debug func in bufferdict