* test=develop,test=coverage, support coverage CI on x86 server

* test=develop,test=coverage, fix the conflict

* test=develop,test=coverage, add target code_coverage

* test=develop,test=coverage, modify the coveralls.cmake

add assign,equal,fill_constant_batch_size_like,range,reduce_prod,cond…  … …itional_block cpu op (#1783)

* add assign,equal,fill_constant_batch_size_like,range,reduce_prod,conditional_block cpu op

* 1.fix roi_perspective_transform,lod_reset,multiclass_nms,slice,while op
2.elementwise_add compute support int input
3.scale compute support int64_t input

* add slice cpu op

* print error var name && print op position

* add exp cpu

* add exp cpu

* prune faster depthwise

* fix style

* enhance scripts

* fix crash of tensor float * constructor

* fix fast check

* fix style

* add model obfuscate feature

* fix style

* fix array length bug

* add merge.sh to merge static library into one combined library

* disable OpenMP for iOS

* support creating tensor with raw pointer.

* fix style

* fix fpga compilation error

* add auto debug tools

* fix style

* develop nearestinterp op  fix bug in element add close #1647

* remove log
remove log

* add comments for imagetools

* format code

* format CMakeLists

* BugFix: lacking of header file of memset, strlen, stable_sort, n_copy

* Update ARM Linux CPU, GPU build docs for rk3399

* FPGA refactor

* disable FPGAKD

* recover misdeleted code segment

* Clear no persistable tensor array before predicting, fix crash when predicting with gpu debugging mode

* Fix code style

* Add fetch API for java, refine android log