GitLab

* [legacy] move engine to legacy

* [example] fix seq parallel example

* [example] fix seq parallel example

* [test] test gemini pluging hang

* [test] test gemini pluging hang

* [test] test gemini pluging hang

* [test] test gemini pluging hang

* [test] test gemini pluging hang

* [example] update seq parallel requirements

* [tutorial] added synthetic data for sequence parallel

* polish code

* Add handson to ColossalAI.

* Change names of handsons and edit sequence parallel example.

* Edit wrong folder name

* resolve conflict

* delete readme