* fix requant relu6 bug

* fix

* delete pipeline change in forward/forward_inplace avoid race in multithreading

* use Mat class for Shape description

* shape specialization constant in compute shader

* wip

* wip

* test forward_inplace, add binaryop unaryop sigmoid test

* fix arm unaryop test

* fix arm binaryop test

* make shape hint optional, cast int8 to fp32, add cast test

* wip

* follow the good and old local size setting for conv1x1

* the optimal local size rewrite

* fix build on msvc

* add permute shader for all packing layout, add permute test

* concat and slice patial shape constant, slice test

* fix slice test

* interp test

* add lrn test, test packing layout implicitly

* add eltwise test

* add normalize test

* add instancenorm test

* reorg shape constant

* simple local group size partition

* add shape constant param

* Fix warnings C4244, C4267 in src/layer/yolov3detectionoutput.cpp

C4244: '=': conversion from 'int' to 'float', possible loss of data
C4244: 'initializing': conversion from 'float' to 'int', possible loss of data
C4244: 'initializing': conversion from 'double' to 'float', possible loss of data
C4244: 'return': conversion from 'double' to 'float', possible loss of data
C4267: 'argument': conversion from 'size_t' to 'int', possible loss of data
C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data

* Fix warnings C4244, C4267 in src/layer/yolodetectionoutput.cpp

C4244: '=': conversion from 'int' to 'float', possible loss of data
C4244: 'initializing': conversion from 'float' to 'int', possible loss of data
C4244: 'initializing': conversion from 'double' to 'float', possible loss of data
C4244: 'return': conversion from 'double' to 'float', possible loss of data
C4267: 'argument': conversion from 'size_t' to 'int', possible loss of data
C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data

* Fix warning C4244 in src/layer/quantize.cpp

C4244: 'initializing': conversion from 'double' to 'int', possible loss of data

* Fix warnings C4244, C4267 in src/layer/detectionoutput.cpp

C4244: '=': conversion from 'int' to 'float', possible loss of data
C4244: 'initializing': conversion from 'double' to 'float', possible loss of data
C4267: 'argument': conversion from 'size_t' to 'int', possible loss of data
C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data

* Fix warning C4244 in src/layer/roipooling.cpp

C4244: 'initializing': conversion from 'double' to 'int', possible loss of data

* Fix warning C4244 in src/layer/sigmoid.cpp

C4244: '=': conversion from 'double' to 'float', possible loss of data

* Fix warning C4267 in src/layer/slice.cpp

C4267: '=': conversion from 'size_t' to 'int', possible loss of data
C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data

* Fix warning C4267 in src/layer/softmax.cpp

C4244: '=': conversion from 'double' to 'float', possible loss of data

* Fix warning C4244 in src/layer/interp.cpp

C4244: '=': conversion from 'float' to 'int', possible loss of data
C4244: 'initializing': conversion from 'double' to 'int', possible loss of data

* Fix warning C4244 in src/layer/instancenorm.cpp

C4244: 'initializing': conversion from 'double' to 'float', possible loss of data

* Fix warning C4244 in src/layer/deconvolutiondepthwise.cpp

C4244: '=': conversion from 'double' to 'float', possible loss of data

* Fix warning C4244 in src/layer/convolutiondepthwise.cpp

C4244: '=': conversion from 'double' to 'float', possible loss of data

* Fix warning C4244 in src/net.cpp

C4244: 'return': conversion from '__int64' to 'int', possible loss of data
C4267: 'argument': conversion from 'size_t' to 'int', possible loss of data
C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
C4267: 'return': conversion from 'size_t' to 'int', possible loss of data

* Fix warning C4244 in src/layer/bnll.cpp

C4244: '=': conversion from 'double' to 'float', possible loss of data

* Fix warning C4267 in src/layer/concat.cpp

C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data

* Fix warning C4267 in tools/mxnet/mxnet2ncnn.cpp

C4244: 'initializing': conversion from 'double' to 'float', possible loss of data
C4267: '=': conversion from 'size_t' to 'int', possible loss of data
C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
C4305: 'initializing': truncation from 'double' to 'float'

* Fix gcc 9 compilation failure

* Fix compilation failure on linux gcc

* Fix compilation failure on old gcc

* Remove C++11 requirement

* initial the ncnn post training quantization tools

* clear some comments of tools

* fix the Travis ci compiler error

* Fix crash issue during load_model

* Fix crash issue during load_model 2nd part

* add the armv7a conv3x3s1 implement without overflow,remove old codes

* fix the bug of conv3x3s2 packed int8

* new int8 implement,weight quant by perchanel,better accuracy~

* fix the bug of conv3x3s1 packed int8 neon

* add the naive c fp32 and int8 winograd F(2,3)

* add the neon intrinsic int8 winograd F(2,3)

* optimize the armv7a int8 winograd F(2,3) with neon assembly

* optimize the armv7a int8 winograd F(2,3) input transform with assembly.

* add the requantize layer and int8 relu implement.

* add graph optimize conv1x1s2 -> conv1x1s1,begin optimize int8 aarch64.

* fix int8 bugs

* add the c naive im2col with sgemm

* add aarch64 int8 winograd f23, conv3x3s2 naive implement

* add the int8 sgemm conv7x7s2 on x86/armv7a platform

* optimize the int8 sgemm by neon intrinsic and packed kernel

* optimize the int8 sgemm with packed data

* optimize the int8 sgemm with armv7a neon assembly

* add the int8 sgemm on arm64-v8a platform

* perpare to merge latest codes from master

* add the int8 param files

* In the Class Net,add the fuse_network method