Move creating transaction request parameters to Transaction module

[BogdanDidenko]

Removed code duplicates. Encapsulate creating transaction parameters in Transaction module

[qywang2012]

@BogdanDidenko Thanks the PR, but API and admin need not require the transaction module, because we have neb-light and neb package library, they need not depend on lots of cryptos libraries.

[BogdanDidenko]

It's bad solution because in all places you have the request structure

tx = {
        "from": options.from,
        "to": options.to,
        "value": utils.toString(options.value),
        "nonce": options.nonce,
        "gasPrice": utils.toString(options.gasPrice),
        "gasLimit": utils.toString(options.gasLimit),
        "contract": options.contract,
        "binary": options.binary
};

And If you change some commands or parameter type on server you should change it in all places. And this approach can have potential problems with backward compatibility and cetera

[qywang2012]

Yeah, We may need a util or parameter js file to handle the parameters check.

[BogdanDidenko]

Maybe some validation module with strategies for different types of parameters.

[qywang2012]

Later We can add the validation module.

[BogdanDidenko]

Yes. It's not top-priority task.