* [LITE][OPENCL][Image]optimise conv2d 5x5 7x7,test=develop

* [LITE][OPENCL][Image]optimise conv2d 5x5 7x7,test=develop

* [LITE][OPENCL][Image]optimise conv2d 5x5 7x7,test=develop

* replace vlog with log in pool, add each run duration print in test. test=develop

* change layout file path. test=develop

* fix act, layout image kernel. test=develop

* fix spell error. test=develop

* remove clfinish in act, concat, layout, nearest_interp. test=develop

* add RELU macro define in fc opencl kernel. test=develop

* add cpu_ref print in activation opencl kernel.test=develop

* fix layout ut. test=develop

* replace log with vlog. test=develop

* fix get output. test=develop

* [LITE][OPENCL][Image] conv 1x1 5x5 7x7 suite

# Conflicts:
#	lite/kernels/opencl/conv_image_compute_test.cc

* [LITE][OPENCL][Image] conv 1x1 5x5 7x7 suite,test=develop

* [LITE][OPENCL][Image] conv 1x1 5x5 7x7 suite,test=develop

* [LITE][OPENCL][Image] conv 1x1 5x5 7x7 suite,test=develop

* [LITE][OPENCL][Image] conv 1x1 5x5 7x7 suite,rm1x1 old,test=develop

[LITE][OPENCL] support fp16 for cl_image_converter, layout, activation all OpenCL image kernel. test=develop (#2964)

* [LITE][OPENCL] support fp16 for cl_image_converter, layout, activation image kernel. test=develop

* add conv, depthwise and UT. test=develop

* add pool, conv, nearest_interp kernel. test=develop

* support fp16 for scale, reshape, concat, fc buffer opencl kernel. test=develop

* refactor for mul opencl buffer kernel. test=develop

* support fp16 for elementwise_mul opecl image kernel. test=develop

* support fp16 for elementwise_mul opencl image kernel. test=develop

* support fp16 for ele_add, fuse_ele_add_act opencl kernel. test=develop

* rename io_copy. test=develop

* mobilenetv1,v2 passed on 855. test=develop

* fix opt for opencl. test=develop

* comment All opencl buffer kernels. test=develop

* refactor conv, depthwise into one routing selection. test=develop

* [LITE][OPENCL] Add opencl image2d conv3x3. test=develop

* [LITE][OPENCL][Image]develop 1x1/5x5/7x7 routing in conv_compute ,test=develop

* [LITE][OPENCL][Image]develop 1x1/5x5/7x7 routing in conv_compute ,convert bias filter in prepare for run ,test=develop