Added a graph data structure in units of ScheduleBlock and some necessary operations, such as finding upstream and downstream nodes, and performing operations in the DFS topological order.

test_dot_merger和test_dot_merger_pass在CI和本地环境中会随机出现segmentation fault错误，导致单测随机挂，经排查后发现是ginac库相关的问题，现避免使用MathIsZero绕过

* Clarify cinn/ir dirs [Part1]

* addition of cinn/ir/op dir

* change header inludsion of ir/ir_operator.h to ir/op/ir_operator.h

* merge with develop changes

* relocate libschedule_desc_proto.a

* remove extra ir_schedule_error.cc

* addition for schedule/ir_schedule_error files

* fix clang-format

* 'fix_clang-format'

* fix remaining errors

* format

* empty commit, re-trigger all ci

* empty commit, re-trigger all ci

---------
Co-authored-by: NSigureMo <sigure.qaq@gmail.com>

* feat(cmake): add cmake of cinn

* feat(cmake): add cmake of cinn python test

* feat(cmake): add jit

* feat(cmake): test/CMakeList.txt

* feat(cmake): rebase to develop

* feat(cmake): remove some flags

* fix(cmake): fix cinn's gflags depends

* feat(cmake): add ci scripts of cinn

* feat(cmake): copy code of cinn

* fix(cmake): fix cinn third_party model path

* gflags dynamic dependce

* fix ci build_demo

* tmp update to c++17 of cinn-only test

* fix cinn only with c++17