* add reference of lbfgs

* add reference of lbfgs

* new ir op test v1.0

* fix new ir optest bug1.0

* modify two testcase bug

* add new ir white list & pass test_mean_op.py

* rename white list

* add new_ir_guard

* new ir sum op test all pass

* rename backward.grad as ir_backward.grad

* check place for new ir

* fix test_build_model env bug

* fix test_prim_program backward bug

* change backward to ir_backward in check_appr

* add check_new_ir flag for mkldnn

* clean

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Co-authored-by: Nwangruting <wangruting@baidu.com>