Testing Lvl1: checking that the transaction builder build valid transaction

[NicolasDP]

We need to validate that the transaction builder is actually building valid transactions.

utilising quickcheck, write property tests to validate the building of the transaction is correct.

For example:

• for an arbitrary set of inputs (len <= 255);
• for an arbitrary set of outputs (len <= 256);
• for an arbitrary set of fee parameters

build a transaction

• the result should give a valid, balanced transaction;

it is important to note that the output values is impacted by the total input available and the fee parameters.

relates to epic ticket: #727