ad ops for faster rcnn, including affine_channel, anchor_generator, generate_proposals and roi_align (#1895)

* add ops for faster rcnn

* disable test for generate_proposals and roi_align, test=develop

* remove .swp file

* remove log in tensor slice

* finish the unit test for roi_align, test=develop

* modify cast op, test=develop

* modify cast op and remove warning in argmax_test, test=develop

* test=develop add matmul_op

* use lite::arm::math::sgemm func to implement matmul

* test=develop  pre-commit command to run clang-format

* Revert "test=develop  pre-commit command to run clang-format"

This reverts commit 3f56474f.

* test=develop pre-commit command to run clang-format

* fix building ios tiny publish lib error

* support setting cluster and threads in MobileConfig

* fix build error, test=develop

* fix building server publish error, test=develop

add model_run_test_image
    add range_max_quant op
    add flatten op
    add flatten2 op
fix:
    fix density_prior_box density_size type from float to int
    fix prior_box and density_prior_box some check for get_attr
test=develop