* add distributed auc

* add attr "is distributed" and config it

* add distributed auc

* add batch auc and code format

* code format

* auc optimize

* metric_op optimize

* code clean

* bug fix and code clean

* bug fix and code clean

* code optimize

* code optimize

* api spec update

* Comments optimized

* add mutex

* Revert: add mutex

* remove distribute metric

* remove distribute metric

* spec modifyed

* add annotation, test=develop

* keep API compatibility
test=develop

* hide operator API

* update

* update api.spec

* fix merge

* fix test

test=develop

* some trivial opt

* remove the fix of lod_tensor and shrink_rnn_memory_op

* refine ShrinkRNNMemoryOp

test=develop

test=develop

* add multi_label UT

* rename, fix typo, add fuse_statis check

Also fix MKL-DNN pooling integration for ceil mode

* add nccl2 dist api

* update apispec

* update

* update api spec

* add guide

* "fix doc"

* Update windows_inference.md

Looks like there is a little problem in markdown format writing of head lines

* add ShareLoDs

* refine

* add Is EmptyVarName

* refine Sharedlod

* wip

* clean up

* should fix running with memopt

* add ut

* mark lr schedule op role

* hide lr_schedule_guard

* use op_role_var instead of ufind

* unify dist test name

* wip for py3 support

* fix var deref

* fix python3 mem_opt order

* remove comments

* Add roi perspective transform.

* Add roi_perspective_transform_op.

* Fix code style.

* Add python api and fix doc.

* Fix API.spec

* Fix python api.

* Fix API.spec

* Move src to detection.