##流程图

/*

				*   Empty <- incoming deals
				|   |
				|   v
			    *<- WaitDeals <- incoming deals
				|   |
				|   v
				*<- Packing <- incoming committed capacity
				|   |
				|   v
				|   GetTicket
				|   |   ^
				|   v   |
				*<- PreCommit1 <--> SealPreCommit1Failed
				|   |       ^          ^^
				|   |       *----------++----\
				|   v       v          ||    |
				*<- PreCommit2 --------++--> SealPreCommit2Failed
				|   |                  ||
				|   v          /-------/|
				*   PreCommitting <-----+---> PreCommitFailed
				|   |                   |     ^
				|   v                   |     |
				*<- WaitSeed -----------+-----/
				|   |||  ^              |
				|   |||  \--------*-----/
				|   |||           |
				|   vvv      v----+----> ComputeProofFailed
				*<- Committing    |
				|   |        ^--> CommitFailed
				|   v             ^
		        |   SubmitCommit  |
		        |   |             |
		        |   v             |
				*<- CommitWait ---/
				|   |
				|   v
				|   FinalizeSector <--> FinalizeFailed
				|   |
				|   v
				*<- Proving
				|
				v
				FailedUnrecoverable

				UndefinedSectorState <- ¯\_(ツ)_/¯
					|                     ^
					*---------------------/

	*/

	Empty          SectorState = "Empty"
	WaitDeals      SectorState = "WaitDeals"     // waiting for more pieces (deals) to be added to the sector
	Packing        SectorState = "Packing"       // sector not in sealStore, and not on chain
	GetTicket      SectorState = "GetTicket"     // generate ticket
	PreCommit1     SectorState = "PreCommit1"    // do PreCommit1
	PreCommit2     SectorState = "PreCommit2"    // do PreCommit2
	PreCommitting  SectorState = "PreCommitting" // on chain pre-commit
	PreCommitWait  SectorState = "PreCommitWait" // waiting for precommit to land on chain
	WaitSeed       SectorState = "WaitSeed"      // waiting for seed
	Committing     SectorState = "Committing"    // compute PoRep
	SubmitCommit   SectorState = "SubmitCommit"  // send commit message to the chain
	CommitWait     SectorState = "CommitWait"    // wait for the commit message to land on chain
	FinalizeSector SectorState = "FinalizeSector"
	Proving        SectorState = "Proving"

Empty - 空状态
Packing - 打包状态，多个Piece填充到一个Sector中
PreCommit1 - PreCommit1计算
PreCommit2 - PreCommit2计算
PreCommitting - 提交Precommit2的结果到链上
WaitSeed - 等待随机种子（给定10个区块的时间，让随机数种子不可提前预测）
Committing - 计算Commit1/Commit2，并将证明提交到链上
CommitWait - 等待链上确认
FinalizeSector - Sector状态确定