* add view suffix to read-only classes for flatbuffers, test=develop

* add some write-apis for flatbuffers, test=develop

* split the vector_view, test=develop

* update OpDataTypeTrait, test=develop

* update traits.h, test=develop

* update fbs op_desc, test=develop

* remove header files, test=develop

* add comments, test=develop

* fix dependencies, test=develop

* add flatbuffers, test=develop

* fix cmake codes, test=develop