Add RGB++ L2->L1 Transaction Tag

[poor-defined]

The definition of L2->L1 could be conducted from the statement here, which could be described as following:

Every non-null Type Cells of input cells are without RGB_lock, every non-null Type Cells of output cells are with RGB_lock;
输入侧非null Type Cell 没有 RGB_lock，输出侧非null Type Cell 有 RGB_lock.

[rabbitz]

PR: nervosnetwork/ckb-explorer@10dee3e

[FrederLu]

PR: nervosnetwork/ckb-explorer@10dee3e

Staging verified.

[Keith-CY]

PR: nervosnetwork/ckb-explorer@10dee3e

Staging verified.

Please deploy it to the testnet at your convenience. @rabbitz

[rabbitz]

PR: nervosnetwork/ckb-explorer@10dee3e

Staging verified.

Please deploy it to the testnet at your convenience. @rabbitz

Already deployed to testnet

[FrederLu]

PR: nervosnetwork/ckb-explorer@10dee3e

Staging verified.

Please deploy it to the testnet at your convenience. @rabbitz

Already deployed to testnet

Testnet verified.