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

* support group conv in opencl

* fix style

* 1.add slice, exp, leakyrelu, nearest op placeholder. 2.complete slice and exp op. 3.fix sigmoid op.

* fix style

* add CPU_ARCH info, improve the performance of GEMM1*1s1

* improve the performance of gemm1*1s1_conv_add and gemm1*1s1_conv_add_bn_relu

* improve the performance of slidingwindow_bn_relu,slidingwindow_add,slidingwindow_add_bn_relu,gemm1*1s1_bn_relu,gemm1*1s1_add_relu

* add faster sgemv_notrans_mx1, fix test_fusion_op

* add slice cpu op

* print error var name && print op position

* add exp cpu

* add exp cpu

* add comment

* add comment

* add comment

* add CPU_ARCH info, improve the performance of GEMM1*1s1

* improve the performance of gemm1*1s1_conv_add and gemm1*1s1_conv_add_bn_relu

* improve the performance of slidingwindow_bn_relu,slidingwindow_add,slidingwindow_add_bn_relu,gemm1*1s1_bn_relu,gemm1*1s1_add_relu

* prune faster depthwise

* fix style

* only InferShape when input shape has been changed

* apply input_dim_has_changed_ criterion only when model has one input vector

* add faster depthwise implementations

* fix style

* enhance scripts

* fix crash of tensor float * constructor

* 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 gemm_int8 arm64 version without openmp

* add gemm_int8 arm64 version with openmp