* add paddle.static.setitem

* add some help doc

* support setitem

* support machanism

* add more unittest

* remove usless code

* raise error in static setitem

* fix d2s UT

* remove static only for both-used code

* fix bool set_value in static, fix set_value_op UT

* fix unittests

* [May case some error]: remove inplace-version check

* add two test case for dy2st

* fix function in vision

* fix dy2st setitem support, refine UT case

* fix slice in static_mode

* add ParametersMap

* remove pop

* modify place

* [fix]: variable is also a tensor

* rewrite some ut & remove slicetransformer in dy2st

* solve error in static-mode

* fix ut

* return a result for set_array_write

* fix test_set_value_op_xpu

* code is different in dynamic / static mode

---------
Co-authored-by: NAurelius84 <zhangliujie@baidu.com>
Co-authored-by: NNotHaozi <zhangmenghao@baidu.com>