Optimize transaction and transaction result db

Currently, the storage of transaction and transaction result is not organized well.

The current implementation uses five columns to store data. Two of them are used to store a state trie and a mempool backup. You don't need to change these columns. Other columns are used to store headers, bodies, and extra information. I think they can be optimized.

Below describes the current implementation for those columns.

## HEADER
* block hash => `BlockHeader`
### BlockHeader
| field name | type |
|---------------|--------|
| parent_hash | H256 |
| author | Address |
| state_root | H256 |
| transactions_root | H256 |
| results_root | H256 |
| score | U256 |
| number | u64 |
| timestamp | u64 |
| extra_data | Bytes |
| seals | ...Bytes[] |

## BODY
* block hash => `BlockBody`
### BlockBody
| field name | type | description |
|---------------|--------|----------------|
| header | Bytes | rlp of header |
| transactions | UnverifiedTransaction[] | |

## EXTRA
* block hash => `BlockDetails`
* transaction hash => `TransactionAddress`
* transaction tracker => `TransactionAddress[]`
* block hash => `Invoice[]`
* and epoch transactions which are not used yet.
### Invoice
```
[0x1] or [0x2, error_hint]
```
### TransactionAddress
| field name | type |
|---------------|--------|
| block hash | H256 |
| index | usize |
### BlockDetails
| field name | type |
|---------------|--------|
| number | u64 |
| total score | U256 |
| parent | H256 |