Move fee as static property of the transaction implementation

[nazarhussain]

Expected behavior

With every custom transaction we should be able to specify some distinct fee for it. And that should not involve passing any configuration at application level.

class CustomTransaction extends BaseTransaction {
   static meta = {fee: 100000}
}

That will be accessible through CustomTransaction.meta.fee in element and in framework where ever required.

Actual behavior

Currently transaction fee is defined as constants in the transactions element as well as framework constants. Which makes it impossible to create and register new transaction.

Which version(s) does this affect? (Environment, OS, etc...)

2.0.0

[nazarhussain]

We also look into this endpoint, either to remove the constants or somehow return the fee of custom registered transactions.

https://github.com/LiskHQ/lisk-sdk/blob/86db5cabc562214958d8d1487fb99ddd4ee24903/framework/src/modules/http_api/controllers/node.js#L85-L93

[shuse2]

Superseded by #3860