* [shardformer/sequence parallel] Support sequence parallel for gpt2 (#4384)
* [sequence parallel] add sequence parallel linear col/row support (#4336)
* add sequence parallel linear col/row support
* add annotation
* add annotation
* add support for gpt2 fused qkv linear layer
* support sequence parallel in GPT2
* add docstring and note
* add requirments
* remove unused flash-attb
* modify flash attn test
* modify flash attn setting
* modify flash attn code
* add assert before divide, rename forward function
* [shardformer/test] fix gpt2 test with seq-parallel
* [shardformer/sequence parallel] Overlap input gather and grad computation during col backward (#4401)
* overlap gather input / grad computing during col backward
* modify test for overlap
* simplify code
* fix code and modify cuda stream synchronize
* [shardformer/sequence parallel] polish code
* 1.support sam 2.add fused qkv for nn.Linear
* update utils support set element in list
* overtwrite SamVisionAttention foward to use DropoutForParallelInput
* remove unused code
* add naive optimizer for 3DPlugin/refactor gpt2 shardformer test
* merge tests of PP/DP/TP combinations into one test file
* fix bug when sync grad for dp in HybridPlugin
* update supported precisions for 3DPlugin/fix bug when shifting tp_degree
* improve the passing of lazy_init
* modify lazy_init/use sync_shared_params
* [shardformer] support lazy init
* [shardformer] linear support lazy init
* [shardformer] embedding support lazy init
* [shardformer] norm support lazy init
* [shardformer] fused linear support lazy init
* [test] update shardformer test layer
* [test] shardformer with lazy init fit ddp
* [lazy] hotfix deepcopy of param
* [shardformer] fix bert policy and update test
* [shardformer] fix bloom policy and update test
* [shardformer] fix opt policy and update test
* [shardformer] fix t5 policy and update test
* [shardformer] fix gpt2 policy and update test
* [shardformer] fix llama policy and update test
Bin Jia