* Initial support for XPU
* Fix compiling errors of XPU
* Move XPU op kernel bridges from backends to kernels to fix deps order
* Change the namespace and directory of XPU bridges
* Add XPU SDK
* Fix header files and namespace of XPU SDK
* Add unit tests for relu and conv2d ops
* Restore the modification of paddle_api_test
* Supports simple model which contains only a relu layer
* Add compiling scripts for XPU
* Fix compiling errors of XPU
* Add comments for XPU LoadModel and BuildModel

build x86 dynamic library in ci_build.sh
./lite/tool/ci_build.sh build_test_server

* make inceptionv4, resnet50, googlenet can run on x86 paltform and fix the compare part in x86 unittests, test=develop

* fix googlenet tests for benchmark record, test=develop

* [framework][profile] fix profile dump bug when op is feed and fetch test=develop (sangoly)

* [python api] init add python api test=develop

* Make armlinux compile libpaddle_light_api_shared.so
test=develop

* add static libraries of cuda, test=develop

* update cuda make

* fix benchmark, test=develop

* [NPU] Fix the bug of loading multi NPU models
test=develop

* [NPU] Use lite tensor to store NPU model, fix the management of multi NPU models, support loading NPU model from memory and reduce the modification of framework
test=develop

* [NPU] Remove redundant header files for NPU bridges,
test=develop

* [NPU] fix NPU deps
test=develop

* [NPU] refine the compiling script for NPU
test=develop

* [NPU] remove redundant subdirectory in lite/CMakeLists.txt
test=develop

* [NPU] Fix and refine NPU test case
test=develop

* [NPU] revoke the modification of other non-NPU modules
test=develop

* [NPU] Remove NPU bridges if target is tiny publish
test=develop

* move the method of SetThread and SetPowerMode from MobileConfig into ConfigBase 
* cxxPredictor will support SetThread and SetPowerMode method

* add full_api_static target and fix building errors, test=develop

* fix build errors, test=develop

* fix code style, test=develop

* fix lite/model_parser/pb/var_desc.cc, test=develop

* fix building errors, test=develop

* modify lite/tools/debug/CMakeLists.txt, test=develop

(1)modify tiny publish so to make it excutable
(2)modify the bug of compiling in armlinux
(3)change 3 full publish so into 2

* paddle lite cuda init
can run model with leaky_relu

* add the missing file.
test=develop

* 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